This site contains affiliate links for which we may be compensated.

Glossary of Racing Terms

Don't sound like you don't know what you're talking about next time at the track — These are the terms you need to know...

Term	Definition
AAA	American Automobile Association. This is the large nationwide car club that offers services such as travel assistance, roadside service. AAA was once the organization that sanctioned most of the "legitimate" racing in the United States; its Contest Board
AARA	Antique Auto Racing Association. Sanctions Vintage Open Wheel exhibition racing.
ABC	Refers to the progression of a stock car drivers training or career through three specific series, A-ARCA, B-Busch, and C- (Nextel) Cup.
ABC Money	Awards given to drivers or team owners who participate consistently in a series.
Abrasion	The act of or effects from friction or stress between two surfaces.
ABS	Anti-Lock Braking System. Anti-lock brake systems are designed to sense wheel locking before it occurs and then release the brakes so that loss of control does not occur..
ACCUS	Automotive Competition Committee of the United States. This is an umbrella organization, which includes representatives from CART, NASCAR, IMSA, SCCA, NHRA, USAC, and as of November 1997, the IRL. It handles cross licensing between sanctioning bodies in t
ACES	Atlantic Coast Enduro Series.
Ackerman	The effective change in toe angle as the wheels are turned through their range of steering motion. This value is described in percentages of change. Frequently confused with bump steer.
ACOT	Atlantic Coast Old Timer Racing Club.
ACRL	American City Racing League.
ACT	American-Canadian Tour, a former rival to ASA. ACT was similar to, but smaller than, ASA; they sanctioned similar classes of cars, mainly in the Upper Plains and central Canada. Tom Curley, the sanctioning body's owner, shut it down at the end of the 1995
Adding Spoiler	Changing the direction of a wing or spoiler to add more downforce.
Adhesion	The amount of stick between two surfaces. Adhesion usually applies to objects at rest where traction applies to objects in motion.
Aero	Abbreviation used when referring to aerodynamics.
Aerodynamic Balance	A state of equilibrium between the front and rear aerodynamic downforce.
Aerodynamics	The science studying the forces exerted on racecars surfaces by air in motion and how it affects downforce, drag, and lift.
Aero Grip	Traction provided by down forces applied to the car
Aero Loose	When two cars are close together and the lead car has less air being applied to its rear spoiler. This causes the car to have less rear downforce, which causes it to be loose in the turns.
Aero Push	When two cars are close together and the trailing car has less air being applied to its nose. This causes the car to have less front downforce, less turning ability, which then causes the car to push up the track.
AFCS	American Funny Car Series. Sanctions Drag Racing in the United States. Formally known as United Drag Racers Association.
After Market	Generally, the replacement parts and high performance products market.
AFR	Abbreviation for Air/Fuel Ratio. The mass of air inducted divided by the mass of fuel inducted.
A-Frame	Either the upper or lower connecting suspension piece locking the frame to the spindle.
Agricultural Racing or Excursion	When a car leaves the track and runs through the grass.
AHDRA	All Harley Drag Racing Association.
AHRA	American Hot Rod Association. Sanctions Drag Racing in the United States.
Air Box	Housing for the air cleaner that connects the air intake to the carburetor.
Air Dam	Used to direct or block airflow. Located on lower front valance. Used in front to prevent airflow to undercarriage, intended to prevent turbulence and lift.
Air Filter	Element used to keep particles from entering the carburetor and engine.
Air Foil	A stabilizer, generally used to create down forces, increase stability, and tire-to-track adherence at high speeds.
Air Pressure	The amount of air inside the tire pressing outward on each square inch of tire; expressed in pounds per square inch (psi) or kilopascals (kPa), the metric designation for air pressure. This should be expressed in "cold" or "hot" values and varies with atm
Air Wrench	In general, any power wrench powered by compressed air, but often used to refer specifically to the special power wrenches used to change tires during a pit stop.
AIS	The American Indy car Series, a low-cost series for Indy car racing. This series keeps costs low by using cast-off CART cars and by using an engine equivalence formula allowing teams a wide variety of engine choices. Currently, the series is defunct, but
Alcohol	When used to refer to racing car fuel, nearly always means methyl alcohol, or methanol. Ethanol is very seldom used for racecars (it costs too much), and other types are never used.
Alignment	The state in which all wheels on a vehicle are pointed in the optimum direction relative to the chassis.
All Pro	A touring series for Late Model cars, running mostly in the South. Created by super-promoter Bob Harmon, who sold the rights to the series to NASCAR in 1992. All Pro cars are quick and light, and often have much higher cornering speeds than other racecars
All-Season Tires	Passenger car tires that are designed for use on dry and wet pavement, and also provide traction in snow and ice.
Alphanumeric	A term for describing something using both letters of the alphabet and numbers. Used in describing tire sizes.
Altered	A general description of a racing vehicle featuring an open cockpit, tubular frame, center driving position, and altered, cut down body from a passenger vehicle. Popular altered body styles were originally produced overseas including the Anglia, Fiat, and
Alternate Starter	A practice, which used to be common in oval-track racing but has now just about died out. An alternate starter was the fastest (or sometimes the two or three fastest) among the cars that did not qualify for the race. Many races used to have rules that sub
Alternator	A belt-driven device mounted on the front of the engine that recharges the battery while the engine is running.
AMA	American Motorcyclist Association. Sanctions Motorcycle events throughout the United States.
Amateur	A beginner or novice in the sport. It is the opposite of Professional.
Ambient Temperature	The temperature of the surrounding air.
AMRA	(1) American Motor Racing Association. Sanctions Open Wheel Modified racing in the US and Canada. (2) American Motorcycle Racing Association.
AMSA	American Mini-Sprint Association.
Angle of Attack	The angle of a car or wing relative to the direction of travel.
ANRA	American Nostalgia Racing Association. Sanctions Nostalgia Drag Racing.
Anti-Sway or Anti-Roll Bar	A suspension component that links the left and right side suspension movement together. This is a torsion spring that limits the amount of lean that a vehicle will develop in a turn. It can be used in either the front or rear of a vehicle. It is a primary
AOAS	American Outlaw Action Series.
Apex	The point in a turn where the car is turning most sharply. By definition, the apex is usually the slowest part of the turn; the car slows down into the apex, and then accelerates out of it. (However, this rule is sometimes violated by the use of unusual c
A-Post	The post extending from the roofline to the base of the windshield on either side of the car.
Appearance money	A guaranteed payment from the promoter or sanctioning body to a driver or team just for showing up, regardless of how that driver or team does in the race. Programs with names like "Winners' Circle" or "Appearance Plan" which pay per-race bonuses to drive
Apron	An area on the inside of the track for cars that are going slowly. At high-banked tracks, the apron has less banking, so that cars that aren't up to speed won't slide off. The apron is also used as the approach to the pits, and as the merge-in area for ca
A/R	The size of a turbochargers turbine housing.
Aramid	A synthetic fabric used in some tires that is (pound-for-pound) stronger than steel. Example: Kevlar:
ARCA	Auto Racing Club of America. Sanctions a national Stock car series, and several regional series. Founded in 1953 as the Midwest Auto Racing Club, it has evolved a number of regional racing series in the Midwest and West over the years. Its national series
ARCA Invaders	Derogatory name for NASCAR teams or Drivers that enter in an ARCA Series event.
ARDC	American Racing Drivers Club.
Arm Restraints	Straps that attach to a driver's arms to limit the range of motion of the upper arm and by doing so keep the forearms and hands in the car. Sometimes required in Sprint and Midget racing; these cars are capable of flipping and rolling very violently, and
Armco	A brand name for one brand of corrugated steel barrier widely used for guardrails on highways. In the '70s, many racetracks experimented with using Armco instead of concrete for crash walls. In this application, the steel barriers have been largely unsati
ARPI	Auto Racing Promotions.
ASA	American Speed Association. Sanctions a Stock car series (the ASA Racing Series) that operates mostly in the Midwest and Southeast, although they have enough dates in other parts of the country that their series is usually considered national. Since 1992,
ASCA	Arizona Sprint Car Association.
ASCC	Atlantic Sports Car Club.
ASCoC	All Star Circuit of Champions. Sanctions Sprint car racing in the United States.
ASCS	American Sprint Car Series. Sanctions Sprint Car racing in the United States.
ASCT	Alaska Sprint Tour.
ASM	All Star Midgets. Sanctions Midget and Dwarf car and Modified Lite Racing.
Aspect Ratio	Tire size term used to compare the tire width to the sidewall height. It is a percentage of the sidewall height compared to the tire width.
ASRTS	All Star Race Truck Series.
ASSC	Alaska Sports Car Club.
Assembly	Typical description of a wheel and tire unit. This can include a tube or liner as well.
Associate	A sponsor that puts up a small amount of money for a race team, and consequently gets its name on a less visible area of the car (such as the rear bumper, or the B-pillar between the side windows).
Atmo Engine	Engines, which use natural or atmospheric airflow as opposed to forced induction. NASCAR, Formula One and NHRA Pro Stock cars use "atmo" engines while Indy and NHRA Top Fuel and Funny Car engines use forced induction engines.
ATQMRA	American TQ Midget Racing Association.
Attenuator	A device mounted at the rear of an IRL car to absorb impacts to the rear end. The IRL new cars originally had a problem with the rear of the car being very stiff and transmitting rear-end impacts to the driver, and the attenuator (which is a large block o
Attrition	The rate at which cars drop out of a race, due to mechanical failure or wrecks. Attrition is said to be high when few of the cars that start a race finish it.
Australian Pursuit	An odd form of racing which was popular in the early days of stock car racing, but has just about disappeared now. In Australian pursuit, each car that is passed by any other car during the race is black-flagged and eliminated from the race. The winner is
Autoclave	A complex oven for curing parts made of carbon fiber.
Axle	The pole or shaft on which a wheel turns. Rotating shafts connecting the rear differential gears to the rear wheels. Drive unit connecting the transmission to the front hubs on front drive vehicles:
Back Gate	Literally, the gate on the back stretch at a short track where car trailers or transporters are let into the pits or garage area, but the term is used by promoters to mean the number of cars and teams that actually show up and attempt to qualify for a rac
Backing It In	Term used to describe a non-wing sprint car's entry into a corner. The car enters the turn in a slide with the rear of the car leading the front of the car. Also refers to a crash involving the car going back first into the wall.
Back Pedaling	Most commonly used in drag racing, the magical art of a driver easing out of the throttle to regain traction and avoid or stop tire shake. Difficult to achieve, the driver must anticipate the problem and pedal before the car is too far out of shape, all i
Back Marker	A car that is many laps behind in a race. Also used as a derisive term to refer to drivers who are consistently slower then the majority of the field.
Back Out or Back Off	When a driver takes his foot off the gas pedal and slows down.
Back Stretch	The straightaway on a common oval track found between turns 2 and 3 on the opposite side from the start/finish line.
Backup Car	A complete second car used if a team
BADGER	Badger sanctions Midget racing.
Bag Tank	Deformable fuel tank made from high strength rubber that is designed to flex and not rupture during an accident.
Balaclava	See head sock. Nomex or fireproof fabric for head and face protection:
Balanced	The state in which a tire and wheel spin with all their weight distributed equally. Also refers to a cars setup being correct.
Ballast	A controlled amount of weight, functionally positioned, used to help car meet class weight requirements.
Ball Joint	A component of the front suspension consisting of a ball mounted in a socket that allows steering control in a stock car.
Bank/Banking	As applied to racetracks, the angle from the horizontal at which a corner or straight is tilted. Banking a corner increases cornering speed by converting some of the sideways centrifugal force to downward force, in much the same way that an airplane banks
Barge Board	Aerodynamic device placed in front of the sidepods or a suspension piece to smooth the airflow.
Barnstorming	Staging of an informal series of races by a touring group, often on temporary or jury-rigged racetracks. Many barnstormers engaged in hippodroming. A popular form of racing in the '30s and '40s when race cars were rare and sanctioning bodies were rarer, b
BCRA	Bay Cities Racing Association.
BDC	Abbreviation for Bottom Dead Center. The position of the piston at the bottom of its stroke.
Bead	A round hoop of steel wires, wrapped or reinforced by ply cords, that is shaped to fit the rim; holds the tire onto the rim.
Bead Lock	A device used on some short-track racing cars to positively fasten the tire bead to the wheel rim. Particularly with low-pressure tires often used on dirt tracks, a bead lock keeps the tire on the wheel, and prevents the tire from slip rotating around the
Bead Wire	The steel wire wrap that is used to construct the bead package.
Beauty Bar	Design treatment that typically separates the sidewall from the shoulder of a tire.
Behind the Wall	Referring to taking a car into the garage area behind the pit wall to do major repairs.
Bell Housing	A cover shaped like a bell that surrounds the flywheel and clutch that connects the engine to the transmission.
Belly Pan	Generally, a skin of aluminum or fiberglass used to cover the under carriage of vehicle, assisting in preventing turbulence and air drag.
Belt	A rubber-coated layer of cords that is located between the plies and the tread. Cords may be made from steel, fiberglass, rayon, nylon, polyester or other fabrics.
Belted Bias Tire	A pneumatic tire with a body similar to that of bias tires, but which also includes two or more belts under the tread.
Belt Line	The line running around a cars body formed by the bottom edges of its glass panels.
Belt Package	The entire grouping of belts in a tire.
Bench Racing	Talking about racing; what racers and race fans do in the winter, or any other time when there's no real racing going on.
Bend	A shallow turn in the track.
BGN	The NASCAR Busch Series, previously known as the Busch Grand National. A Stock car series sanctioned by NASCAR. The cars are similar to Winston Cup cars, the main differences being smaller carburetors, less horsepower, and prohibitions on exotic materials
Bias Ply Tire	Bias Ply tires are constructed of layers of rubber-coated plies composed of textile cords placed upon each other at approximately 30-45 degree angles. These plies are then wrapped around the bead wires. As a result of a tire being bias in design it will h
BIDCA	Badger-Illini Classic Modifieds.
Big Block	As used today, usually refers to a big-block Chevy engine, although in context it can refer to a big-block engine from any manufacturer. Background: In the 1960, American manufacturers commonly sold all cars except for their economy lines with V-8s; engin
Big One, The	Refers to a wreck involving many racecars during a race usually at one of the bigger speedways such as Daytona or Talladega.
Billet	Raw material form of forged metal that can be machined.
Binders	Another name for brakes.
Bite	The amount of grip the tires or car has with the track.
Black and Red Flags together	Indicates the end of a practice or qualifying session. All cars should exit the track and go to the pits or garage area. Checkered and red, or checkered and black, flag combinations may also be used.
Black Box	In car high tech electrical systems. These would control most engine functions. More technically referred to as the Engine Electronic Controls, the Engine Control Unit or the Engine Management System. May also include measure devices to record information
Black Flag	Report to the pits. Used to call in a car, either because the team is to be penalized, or because the car presents some sort of hazard that must be fixed (e.g., leaking oil, loose bodywork, or going too slow). Generally, the driver has a small number (2-3
Black Flag with White	Signals a racer that is ignoring a black flag that if he/she does not come in they will cease scoring that car.
Black Slick	A condition describing a dirt tracks surface when it still has enough moisture to keep the material packed, but has hardened and is taking rubber.
Blade	Term that some drivers use for a rear spoiler.
Bladder	Device that contains the fuel and keeps it from spilling and catching fire in the case of a rear impact.
Bleach Box	Section of track before the starting line where cars spin the tires in water. In early drag racing, actual chlorine bleach was used in place of water, originating the name.
Bleeder Valve	This is a device mounted in a wheel. It is a valve that is used to keep air pressure constant during a race. Air pressure increases with heat and this valve opens and releases air until the pressure returns to a preset amount.
Blend Line	Line painted on the track near the apron and extending from the pit road exit into the first turn. When leaving the pits, a driver must stay below it to safely "blend" back into traffic.
Blind Rally	A race in which the route is not released until just before the start.
Blip	A short tap on the throttle.
Blistered	Condition where a tire is run at excessive temperatures causing the tread to turn into a semi-liquid state. This is characterized by visible porosity in the tread, and sections of tread separating from the body.
Blower	Another name for a supercharger.
Block	An area of raised (or surrounded by grooves or sipes) tread on a tire.
Blocking	Racing term for changing position on the track to prevent drivers behind from passing.
Blower Belt	The belt that drives the blower on a dragster. Also see Gilmer Belt.
Blow Over	A drag racing phenomenon where a dragster, most often a Top Fuel car, flips over itself. Excess traction and weight transfer lifts the front wheels, then air pressure under the nose pushes the front end higher until the car eventually topples over itself.
Blown Engine	(1) An engine that has suffered a catastrophic bottom-end failure, such as a broken connecting rod. Engines that have blown usually have suffered irreparable block damage and have to be junked. Blowing an engine frequently produces a huge cloud of smoke a
Blue Oval	Refers to a Ford. The name comes from the shape of its logo.
Blue with Yellow Stripe Flag	A signal to lapped cars to move out of the way of faster cars. The actual rules associated with this flag vary considerably. In some series, a driver can be penalized for ignoring this flag; in others, it is strictly an advisory (and in fact, the flagman
Blueprinting	The meticulous matching to factory specifications all parts and/or components. Dressing parts to absolute design callout or manufacturer's specifications.
B-Main	A second-chance race sometimes seen at an event that uses heat races to determine qualifying and starting positions for the feature. The B-main includes all cars that failed to finish in a qualifying position in their respective heat races, and a certain
BMARA	Badger Midget Auto Racing Association.
Board Track	An oval track whose surface and foundation are made from wood. Elaborate board tracks were constructed in the 1910's and '20s, mainly on the West Coast, in part because good paving materials for earthen works tracks were not available (modern asphalt havi
BOB	Battle of the Bluegrass Tour.
Bobble	A slight wiggle or a brief lose of control that is recovered by the driver.
Bolt-On Parts	Term used to describe the parts that attach to the car's chassis.
Bomber	A Stock car class where old cars (often retrieved from junkyards) are raced, with few or no modifications allowed. Intended to be the absolute lowest-cost way of going racing at many tracks, but they also have the side benefit of providing a measure of co
Boost	The amount of pressure generated by a turbocharger or supercharger as it forces the air/fuel mixture into a forced induction engine.
Bore	The diameter of an engine cylinder.
Bottom Dead Center	The position of the piston at the bottom of its stroke.
Bottom End	The reciprocating and rotating parts of an engine that transmit the engine's power, including the pistons, crankshaft, connecting rods, and main bearings. See also top end.
Bow Tie	(1) Chevrolet, from the shape of its logo. (2) A series of cylinder heads made by Chevrolet for racing, mainly for use by Late Models and drag racers.
Box	Slang term for a transmission.
B-Post	Post extending from the roofline to the base of window behind the driver's head.
Brain Bucket	Slang term for a helmet.
Brake Duct	A tube that takes air from the front or side of a car and directs it to the brakes in order to cool them.
Brain Fade	A lack of focus that can lead to making a mistake during a race.
Brake Balance	The difference in braking force between one end or side of the car, and the other. Racing brake systems are usually designed so that the front-rear brake balance can be adjusted, with more force going to one end or the other as desired to improve handling
Brake Fade	Condition that occurs when the brakes get so hot they are ineffective and braking power is reduced.
Brake Tuning	Using both braking and steering ability of the car between the turn in point and the apex of a turn.
Breakout	(Run Under) In Drag racing, when your elapsed time is quicker than your dial-in, this causes you to be disqualified.
Break Loose	Describes when the tires are pushed beyond their threshold and they lose traction.
Brickyard	Nickname given to the legendary Indianapolis Motor Speedway, which although paved now, used to have a brick surface.
Buildup	Term use to describe an increase in tire pressure due to the tire heating up (by running and brake heating) and internal humidity turning into steam. To help limit pressure buildup teams use nitrogen dried air, or other gas to lower internal humidity.
Bull Ring	A general term for a short track usually a half-mile or less where local weekly races are held.
Bump Drafting	A drafting technique where a trailing car that is rapidly gaining on a preceding car will actually hit the preceding car in the rear (gently), in order to transfer some momentum to the preceding car and speed it up, which because of the dynamics of drafti
Bump Rubber or Bump Stop	A piece of rubber used to stop the travel of the suspension.
Bump Steer	Un-commanded steering motion in a front wheel, caused by the wheel's changing its toe angle as it moves up and down. Usually considered undesirable. Great effort is made to minimize the condition by changing the geometry between the steering rack and the
Burn Off	Burning fuel during the course of a race. As fuel is burned, the car becomes lighter and its handling characteristics change, challenging the driver and crew to make adjustments to achieve balance.
Burned Piston	A type of engine failure, which is the result of pre-ignition or excessive heat in a cylinder, usually because the air-fuel mixture has become too lean for some reason. (Alcohol-fueled engines are especially vulnerable to this.) A burned piston has its to
Burnout	Spinning of rear wheels at high RPM to heat and clean drive tire rubber prior to a run, resulting in increased traction.
Busch	The NASCAR Busch Series, previously known as the Busch Grand National. A Stock car series sanctioned by NASCAR. The cars are similar to Winston Cup cars, the main differences being smaller carburetors, less horsepower, and prohibitions on exotic materials
Busch Whackers	Derogatory name for Nextel Cup teams or Drivers that enter in a Busch Series event.
Bye Run	In Drag racing, a lone run given to a randomly chosen car, because of an unequal number of cars in the round.
Calendering	A machine process that combines body-ply rubber and cord fabric together into a specified thickness.
Calipers	A component of the braking system that houses the piston, which hydraulically pushes the brake pad against the rotor.
Camber	One of the three major front suspension geometry adjustments. The camber angle is the angle between the plane of the wheel (think of it as the plane of the hub face, or the brake rotor), and the vertical. Negative camber is when the top of the wheel is le
Can-Am	Sanctions TQ Midget racing on asphalt oval tracks.
Cantilever	This is a tire designed to increase the tread width when rules restrict the rim width. The most noticeable characteristic is the pronounced sidewall extension. These tires typically present a challenge to the service technicians when mounting and dismount
Cap	A metal or plastic screw on cap for the valve stem.
Carbon Black	Ingredient used in the manufacturing of tires. Acts as a filler but also adds strength and color to a compound.
Carbon Monoxide	Colorless, odorless poison gas created by the combustion of carbon-based fuels.
Carburetor	A device mounted on top of the intake manifold that controls the air-fuel mixture going to the engine.
Carcass	The tire body beneath the tread and sidewalls; also called casing.
CARS	(1) Championship Auto Racing Series. (2) Classic Auto Racing Series.
CART	Championship Auto Racing Teams, one of the two organizations that sanctions Indy car racing.
CASA	California Asphalt Sprint Association.
CASC	Canadian Automobile Sport Clubs.
CASCAR	Canadian Association for Stock Car Auto Racing.
Casing	The tire body beneath the tread and sidewalls.
Caster	It's the angle between the front wheel kingpin and the vertical when viewed from the side. (Think of it as the "hinge" that the wheel swings on when the steering wheel is turned). All modern suspension designs have the top of the kingpin leaning toward th
Catch Can	A small can that is used to catch fuel that comes out of the fuel cell vent when it overflows (while being filled). Also: Most fuel cells today have a check valve in the vent line that prevents fuel from backing out of the vent line. This valve also preve
Catch Fence	The fence along the wall that protects spectators from errant cars, parts, etc.
Caution	A period when a race is stopped due to an accident or other dangerous situation (such as rain, debris, or spilled oil) on the track. Indicated by the display of a yellow flag and light. The cars may continue moving around the track behind a pace car and n
Caution Lights	At most tracks, a series of signal lights around the perimeter of the track that duplicates the functions of some of the flags. Commonly, old traffic lights containing red, yellow, and green bulbs. Some use strobe or flashing yellow lights in addition to
C.C	Cubic Centimeter, a metric unit of volume measurement, equal to approximately 0.061 cubic inch.
CDCRA	California Dwarf Car Racing Association.
Center of Gravity	A measurement used in chassis setup to determine the overall balance of a race vehicle and adjust handling characteristics. The center of gravity is an imaginary point located in the car where if raised by that point, the car would balance perfectly. Cent
Center of Pressure	The point on an Indy car under-wing, which receives the greatest amount of airflow pressure. This measurement is critical to setting front to rear balance, especially on superspeedways.
C.F.M	Cubic Feet per Minute. A measure of airflow.
Chalk Mark	A measurement of the circumference written on the tire. This is usually not a cold circumference but a measurement taken after the tire has been removed from the mold and inflated. This measurement is used a reference point for comparing tire sizes.
Championship Cars or Champ Cars	(1) Refers to front-engine Indy cars that raced at Indianapolis and other Indy car venues until about 1965. See also Silver Crown. (2) The term that CART began using for its cars in 1998 (after it was barred from using "Indycar" as the result of a lawsuit
Chassis	The frame of a racecar that provides a mounting point for the motor, suspension, steering, roll cage, and drive train components.
Checked Out	Expression when the leader drives away from the rest of the field and will seem impossible to catch.
Check Up	To slow down abruptly, either because of a problem with the car, or because of an incident occurring ahead. When a driver checks up, he/she is supposed to hold up their right hand and wave it, as a signal to following cars, but there isn't always time. Su
Checkered Flag (black and white)	The race is over. This flag is always shown first to the winner; each car gets to complete the lap that it is on, and then the race ends.
Chicane	An "S" like track configuration generally designed on a fast portion of a track to slow cars. Also referred to as "esses" or a "switchback.":
Chili Bowl	A nationally recognized indoor Midgets race in Tulsa, Oklahoma.
Christmas Tree	An electronic starting device used in drag racing that incorporates calibrated lights displaying a visual countdown for each driver, activated by a designated official. See full and pro tree.
Chrome Horn	Bumping into the rear of the car ahead of you, to cause him to get a bit loose (so he'll slow and you can pass him), or just to express dissatisfaction with his driving. The term comes from the early days of Stock car racing, when the racecars were showro
Chromoly	Also Chrome Moly. Short for Chromium Molybdenum steel. Very strong and light tubing highly adaptable for racecars.
Chunking	Condition in which rubber comes off a tire in chunks due to the tire being chemically treated or a bad or misused compound.
Chute	(1) Short for parachute or drag chute. Used to assist high-speed braking. (2) A straight away on a track.
C.I.D.	Cubic Inch Displacement. A measure of volume, used to measure cylinder volume.
CIFCA	California Independent Funny Car Association.
Circuit	Any racetrack. Also refers to the entire slate of races on a season schedule.
Circulating	Driving around a track with a damaged and/or slow car to accumulate laps and, more importantly, points and prize money.
Circular	A track with no straights. There have been such tracks in the past; the old Reading, Pennsylvania track was a well-known example in its day. There are no significant circular tracks existing today. (However, Flemington, New Jersey, is a rectangular track
Circumference	The measured distance around the tread portion of a tire.
Claim Rule	A rule that allows parts from one competitors' car to be purchased by other competitors at a set price. Usually applied to engines, claim rules supposedly keep the cost of racing down by making it unprofitable to spend a lot of money on illegal or exotic
Clean Air	Air without turbulence created in the wake of other racecars.
Clevor	Name for a Ford production-based small-block V-8, which is the basis for the current Ford NASCAR Winston Cup engine. The engine is an amalgam of the best features from the "Cleveland" and "Windsor" engines of the '70s, and the "Clevor" name is a combinati
Clip	On a tube-frame Stock car, the front and rear sections are designed so that if they are damaged in an accident, they can easily be cut off (with a cutting torch) from the main part of the chassis, and a new section welded on. These replaceable sections ar
Clipping	(1) Minor contact between racecars. (2) Refers to hitting precisely, or "clipping," the apex of a turn.
CLMA	Colorado Late Model Association.
Closed Wheel	A racecar where the suspension, wheels and tires are mostly covered by the body.
Clutch	The coupling device that when engaged or disengaged connects or disconnects the engine to the transmission.
Clutch Can	Bell housing, the bell-shaped housing used to encase clutch and flywheel.
Clutch Lockup	The progression of the clutch-disc engagement controlled by an air-timer management system.
CMT	Carolina Modified Tour.
CNYMS	Central New York Mini-Sprints.
Cock Pit	Area in a car where driver sits.
Cold Inflation Pressure	The amount of air pressure in a tire, measured in pounds per square inch (psi) before a tire has built up heat from driving.
Cold Pits	When there is no racing activity on the track and the pits are open to people other than team members and racing officials.
Collected	Getting hit by an out-of-control car while trying to pass by or through an accident in progress.
Combinations	A teams groups of engines, gearings, suspensions, aerodynamic parts, and wheel and tire settings that they forecast will work under varying conditions and tracks. These combinations (also known as set-ups) are recorded and used as baseline when teams arri
Combustion	The burning of the fuel-air mixture in an engine cylinder.
Combustion Chamber	The part of the cylinder within an engine block where the fuel/air mixture is compressed by the piston and ignited by a spark from the spark plug.
Come In/Coming In	When a tire gets up to temperature and begins gripping. May also be called
Competition Area	The staging lanes and racetrack surface.
Competition Yellow	A scheduled caution period during a race. It has the effect of drawing all the cars together, which can prevent the race from becoming a "runaway"; it also de-emphasizes the importance of pit stops by decreasing the number of pit stops that must be made u
Compound	This refers to the mixture or durability of the rubber on the tread of the tire. Compounds are usually described as "hard" or "soft". The more abrasive the track is the harder the compound you would want to use.
Compression Ratio	The volume of the combustion chamber and cylinder when the piston is at the bottom of its stroke, divided by the volume of the combustion chamber and cylinder when the piston is at the top of its stroke. Higher compression ratios tend to increase engine e
Compressor	A machine that pressurizes and regulates airflow for delivery into tools or tires.
Connecting Rod	A metal rod used to connect the piston to the crankshaft.
Consolation Race	Sometimes called the "consy," this is a race for teams who fail to qualify for a feature race or main event. (Some people incorrectly use this term to refer to a B-main.) The consolation typically will come with a small amount of prize money for the top f
Constant Radius Corner	A turn that has the same radius throughout the turn.
Contact Patch	The area of a tire that is in contact with the ground.
Contingency Awards	Money or prizes that are awarded to race participants by parties other than the race promoter. The contingency award may be based on performance, on a team's use of a sponsor's product, or any other criteria that the party sponsoring the award feels like
Cool Down Lap	A lap run after taking the checkered flag in order to slow down before leaving the track.
Co-opertition	Slang term that combines the two words Cooperation and Competition. Describes the act of teams cooperating during competition. The best example is drafting at superspeedways to benefit both cars.
Cord	The strands of material forming the plies or layers of the tire. Cords may be made from fiberglass, rayon, nylon, polyester, steel or other materials.
Core	The mechanism in a tire valve stem that allows one-way passage of air. Also called "valve core".
Cornering Force	The sideways force or lateral gravitational (G
Corner Worker	Racetrack or series safety staff that are located in the corners to notify drivers of any dangerous situations in the area.
Cosmetic Damage	A spot or location of damage that is not a structural problem to the operation of the tire.
Cowl	A removable metal scoop at the base of the windshield and rear of the hood that directs air into the air box.
Cowl Induction	Housing for the air cleaner that connects the air intake at the base of the windshield to the carburetor.
C-Post	The post extending from the roofline of a racecar to the base of the rear window to the top of the deck lid.
Crankcase	The area of the engine block that houses the crankshaft.
Crankshaft	The rotating shaft within the engine that delivers the power from the pistons to the flywheel, and from there to the transmission.
Crash	An incident where one or more cars are involved in a wreck.
Crash Clause	A special provision that is included in a racecar rental contract regarding the amount that the renter will pay the owner if the racecar is wrecked.
Crate Motor	In some series such as ASA, a similar motor is supplied to all competitors. This is mainly done to reduce costs and even the competition, similar to a specified tire rule.
Crew Chief	The individual responsible for all mechanical aspects of the racecar and strategic decisions during pit stops and the race.
Cross Weight	The percentage of weight on the right front vs. the left rear wheel.
Crossed Flags	(two flags furled and crossed in an X shape): Indicates that half of the distance of the race has been completed. Usually, in oval-track racing, the rules stipulate that once one-half of the scheduled distance has been completed, if some condition (such a
Cross Thread	Stripping of the wheel stud threads when crewmembers hurriedly refasten lug nuts.
Crush Panel	On a tube-frame Stock car, a sheet metal panel that fills in the gaps between the firewall and the side body panels. If the crush panel gets damaged, engine heat (and frequently exhaust gas) comes into the cockpit, which can make the driver extremely ill.
CTS	Craftsman Truck Series.
Cure	The process of putting a completely assembled green tire in a press and forming into a finished tire.
Cushion	Area of the corner above the farthest outside groove on a dirt track where loose dirt builds up.
Cut	A sharp turn or a racecars ability to negotiate a turn. The car is cutting well means the car is able to turn well.
CVM	Canadian Vintage Modifieds.
CVSCRA	Carolina Vintage Stock Car Racing Association.
Cylinder	A chamber in the engine in which combustion occurs and drives the piston.
Cylinder Head	The top or lid over the cylinder(s).
Cylinder Liner	A circular housing that the piston moves in when the cylinder is not an integral part of the engine block. Also referred to as a
DAARA	Daytona Antique Auto Racing Association.
Damper	Device used to restrict the travel of a part usually a spring.
Darlington Stripe	A streak of scraped-off paint that appears on the right side of a car, from having made light contact with the outside wall. The term originated at Darlington back in the '60s, when the track had Armco for its retaining walls.
Dash	An event that is usually six to eight laps in length. Starting lineup of this event is usually determined by combination of Qualifying and Heat Race results. The finishing order of this event usually determines starting order of the first three or four ro
Date TIN	The alphanumeric mark located above the tire bead on the reverse sidewall. The actual "Date" portion of the TIN is only visible on DOT type tires.
Dead Pedal	A footrest found to the left of the operating pedals to give the driver a place to put his left foot during hard cornering.
De-Beading	This is when a tire dismounts from a rim. This is normally caused from low air pressure.
Decals	A tradition as old as Stock car racing itself. Decals are a low-budget form of advertising that sometimes provides rewards that are small, yet important to struggling teams. Contingency awards are sometimes tied to the display of decals.
Deck Lid	The trunk lid. On most Stock cars, the trunk is vestigial, but the lid remains for access to the fuel cell, oil tank, battery, and other things that might be stashed away in that space.
Decreasing Radius Corner	A turn that has a smaller radius during the last half of the corner.
Deep Staging	In drag racing, when the racer inches his car forward, not completely passed the starting line (staging line) so much as to turn off the pre-stage light. This technique is often used to break the concentration of your opponent at the line. Deep staging in
Defect	A general description of a manufacturing flaw. This could be cosmetic or structural in nature.
Delamination	Visible circumferential lines that occur when spiral tread wraps open up. This condition is usually cosmetic but in extreme conditions can be a performance problem.
Depth Holes	Cavities located in the tread surface that enables wear measurements.
Detroit Locker	A brand name of a ratcheting (limited slip) rear end commonly used in Winston Cup.
Dialed In	When a cars setup is in an ideal state.
Dialing In	The driver and crew making setup adjustments to for better handling.
Dialing Under	Allows competitors in Stock and Super Stock the option of selecting a time faster than the National Index. Applied in handicap elimination racing where breakout is in effect.
Dial-ins	Driver's predictions of E.T.'s their cars will run in their first eliminations.
Diameter	The height of the tire (usually unloaded).
Diamonding	Taking corners by driving into the corner fairly straight, making a sharp turn in the middle of the corner, and then driving out fairly straight (such that, as the car goes through the corner, it moves from the inside to the outside and then back to the i
Diaper	A blanket made from ballistic and absorbent material, often Kevlar, which surrounds the oil pan and serves as a containment device during engine explosions. Also used to prevent fluid leaks from damaging racing surface during indoor racing events.
Dicing	Close, exciting driving between 2 or more racers. Positions are exchanged frequently.
Direct Drive	When a drive train is directly connected between the engine/crankshaft and the axle without a clutch.
Directional	Usually refers to a tire that is only to be run one way and not reversed. Indicated by directional arrows. This is due to the construction of the tire. Running a directional tire the wrong way can result in its destruction.
Dirt Track	A track, which is not paved, but rather has a dirt (usually red clay, or some mixture including clay) surface. Dirt tracks host mainly Late Model, Midget, and Modified classes in weekly racing and some touring series. Dirt tracks are nearly always short t
Dirty Air	An aerodynamic term for turbulent air currents caused by fast-moving cars. Can cause a trailing car to lose control.
Dismount	Removing a tire from a wheel.
Displacement	In an engine, the total volume of air/fuel mixture an engine is theoretically capable of drawing into all cylinders during one operating cycle. Described in cubic inches or cubic centimeters.
Disqualification	The most severe during-race punishment that a sanctioning body can impose. Disqualification is imposed only for the most severe infractions, such as ignoring a black flag or deliberately wrecking another car. It may also be imposed after the fact for seve
Dive	The amount the front end of the car lowers during deceleration or braking. Usually before entering a turn.
DNF	Acronym for "did not finish". The opposite of running at finish. Most racing box scores will list, for each car, either "running" or a very brief reason why the car DNF'ed, such as "engine" or "accident".
DNQ	Acronym for "did not qualify".
DNS	Acronym for "did not start". See also alternate starter.
DOHC	Dual Overhead Cam. Engine with two camshafts over a bank of cylinders; generally one cam operates the intake valves, and the other the exhaust valves.
Door Bars	Term used to describe the side protection bars built into most full-bodied racecar roll cages. Often, 3 or 4 horizontal bars are joined to the front and rear upright support bars to form the door bar structure.
Door Car	As the name implies, any drag racing vehicle with functioning doors. Although they resemble passenger vehicles, Funny Cars are not door cars, as their doors do not function.
Dope	(1) Slang term for the homebrew fuel mixtures that were used in Indy car racing in the '20s and '30s. In the days when available gasoline was very low in octane, teams often mixed their own gas so that they could run higher compression ratios. (2) Refers
DOT	Department of Transportation. Governing body that establishes regulations including tire labeling and performance standards of tires that are run inside the United States on public roads and highways.
DOT Markings	A code molded into the sidewall of a tire signifying that the tire complies with U.S. Department of Transportation motor vehicle safety standards. The DOT code includes an alphanumeric designator, which can also identify the tire's manufacturer, productio
DOT Tires	Used to refer to street-legal tires that can be purchased by the public, as opposed to racing tires. Many lower-cost forms of racing require use of Department of Transportation (DOT) tires.
Double	Recent term for competing in the Indianapolis 500, and the Coca-Cola World 600 at Charlotte, in the same day ("running the double").
Doughnut/Donut	(1) Circular patterns that are formed on the side of a car when it comes into contact with the front or rear fenders of another car, and that car's tires (perhaps slightly protruding from the fenders) rub off the paint, forming a circular rub pattern. (2)
D-oval	Type of oval track that has a gradually, continuously curving front "straight". Michigan, Fontana, and Richmond are examples.
Downforce	Refers specifically to downward forces generated by aerodynamics, either due to the car's body shape or due to aerodynamic aids such as spoilers and wings (as opposed to downward force resulting from the car's weight or from G-forces). Downforce resulting
Downshift	Moving the transmission to a lower gear.
Drafting	An aerodynamic phenomenon that occurs at high-speed tracks. A car following another car runs in a partial vacuum left behind the lead car, which means that it doesn't have to use as much power moving air aside. The lead car also benefits, because the foll
Drag	The resistance a car experiences when passing through air at high speeds.
Drag Coefficient	A measured amount of how much drag an object creates while traveling through the air.
Drag Slot	When the starting grid for a race contains an odd number of cars (and assuming that the cars are started two-abreast, which is usually the case in Stock car racing), the last car in the field starts on a row by itself. That car is said to be in the drag s
Drift	A controlled slide through a turn or in an open area. Drifting has become a competitive sport.
Drive Line	All parts included in the drive train not including the engine and the transmission.
Drive Plate	A splined metal plate that transmits the rotation of the axle shaft to the hub assembly on solid axle suspensions. Variations of this design allows for 2-3 degrees of camber in the system.
Driver's Meeting	A meeting which usually takes place 10-30 minutes prior to a major race, conducted by race officials, and which all drivers in the race are required to attend. Often, the meeting is merely a formality, but sometimes it is used to discuss unusual condition
Drive Shaft	The shaft mounted between the transmission and the rear end differential.
Drive Shaft Strap	A U-shaped strap that is fastened to the bottom of the car, and passes beneath the drive shaft. Its purpose is to keep the drive shaft in the car if the shaft or one of its U-joints breaks. Use of drive shaft straps is mandatory by most oval track racing
Drive Train	All parts that supply power to the wheels including the engine, transmission, drive shaft, differential, and hubs.
Driving Away	When a driver is pulling away from the field with little challenge from anyone else in the race.
Droop Limiter	A device that controls downward suspension travel.
Dropping a Cylinder	A generic term for any condition that causes an engine cylinder to stop producing power. In racing engines, this usually results from either an ignition failure, or from a valve failing to open or close properly. (The latter often results in the valve con
Drop the Hammer	When a driver puts the gas pedal to the floor.
Dry Hops	Process of spinning your tires on dry pavement creating off and on contact with the ground.
Dry Line	A clear or dry line on the track that develops after rain because of more frequent use.
Dry Sump	The type of oiling system used on most racing engines. In a dry sump system, oil that isn't being used at the moment is stored in a tank, away from the engine, eliminating the need for the "deep end" on the oil pan.
Dry-Break Connector	A connector used for fueling apparatus (gas cans or hoses) that can be connected or disconnected under pressure without spilling any fuel.
Dry-Slick	A dry dirt track with little or no moisture or grip. Often associated with a dusty track.
Dry Weight	A car's weight without any liquids such as gas and oil.
Dump Shifting	Skipping gears while downshifting.
Durometer	A device used to measure the hardness of the rubber on the surface of a tire.
Dwarf Car	A racing car, with a vintage-replica body (usually of a car from the '30s or '40s) built on a tube-frame chassis, and usually with some type of 4-cylinder engine. Many dwarf-car divisions are spec series, with all competitors being required to purchase th
Dynamic	Dimensions or descriptions that apply when an object (tire, suspension or car) is in use or in motion. (See "static"):
Dynamic Weight Transfer	The transferring of weight from side to side during cornering, from rear to front during deceleration and from front to rear during acceleration.
Dyno	Short for dynamometer. A device used to measure the power output of an engine, in or out of a car, by applying its power to a load. The load is usually some form of brake or friction device (such as a water turbine). The term is often used loosely for any
Early Apex	When a driver turns into a corner too soon.
Economy Run	When a driver drives conservatively to save the engine, fuel and tires.
EEC	Electronic Engine Control.
EGT	The Exhaust Gas Temperature.
EIRI	Except in rare incidents.
EKRL	Endurance Kart Racing League.
Elapsed Time (ET)	The total time it takes to get from the starting line to the finish line. Each car must have its number on the side of the car, in the door area, and on the roof. Small numbers can appear on the nose, in the place where the headlights would be on a produc
Electric Eye	A generic term for any electronic timing device.
Electrical	Sometimes used as an excuse for a car's retirement from a race when revealing the real reason would be embarrassing; for instance, if the engine fails in a race being sponsored by the engine's manufacturer. This type of prevarication isn't very common, fo
Eliminations	When cars are raced two at a time, resulting in one winner and one loser "eliminated." Winner continues to race in a tournament-style competition.
End Plate	The vertical end portion of a wing.
Enduro	A short-track event, which runs at a longer-than-usual distance and with an abnormally large field. In an enduro, the lead cars start to enter lapped traffic after only a few laps. This makes the event more of a challenge to the driver to be smooth and st
Engine Computer	A microprocessor that controls the functions of the engine, such as fuel delivery and engine timing. Almost universal in passenger car engines since about 1985, and Indy car engines have been using them since the late '70s. However, computer-controlled en
Engine Leasing	Process where a race team leases an engine from an engine builder for a specific length of time for a fee. All maintenance, rebuilds, and tuning are handled by the leasing company. Leases usually occur when teams do not have their own engine shop or when
Entry	The line or point a vehicle enters into a turn.
Entry Level	A class of racing with a wide range of rules and types of cars that include Street, Pure, Hobby, Super, Factory, Pony, Mini, and Limited Stocks as well as Bombers, Road Hoggs, Thunder Cars, Cruisers, Roadrunners, some Sportsmen, Runabouts, Chargers, Figur
EOQM	Eastern Outlaw Quarter Midgets.
ERA	Englewood Supermodified Association.
ESDCA	Empire State Dwarf Car Association.
ESS	Empire Super Sprints
Esses	An "S" like track configuration generally designed on a fast portion of a track to slow cars.
E.T.	(Elapsed Time). The total time it takes to get from the starting line to the finish line. Each car must have its number on the side of the car, in the door area, and on the roof. Small numbers can appear on the nose, in the place where the headlights woul
Equalize	To gradually lose pressure in an inner-liner equipped tire, until the main carcass pressure equals the inner liner pressure. When this happens, the inner liner partially unfolds inside the tire and flops around, which can create a severe vibration.
Equal Loading	When two tires on the same axle have the same amount of weight applied or loaded.
F1	Abbreviation for Formula One.
F.I.A	International Federation of Automobile Clubs. Sole international body governing motor sports outside the United States.
Fabricator	Team member responsible for the body of the racecar.
Factory Team	A team owned, operated, or sponsored directly by an automobile manufacturer.
Fall Off	Gradual or drastic deterioration of a tires performance during use.
FASCAR	Florida Association of Stock Car Auto Racing.
Feature	The main event at a weekly-racing session or regional (or, less commonly, a national) event. Typically, a short track running weekly racing will have several classes, and each class has a feature (possibly more than one) where most of the money and points
Fence	Term to describe the barrier on the inside or outside of the tracks racing surface. I may be a wall or steel rail but still be referred to as a fence.
Ferrous	Containing iron, as in metals.
Fidgets	Slang for the Ford Focus Midgets.
Field	The group of cars that starts a race or the total number of cars in attendance. May also refer to the group of drivers and teams that competes regularly in a particular racing series.
Field Filler	Cars that enter an event to fill out the field of entrants. This is done in order for the series or promoter to present the advertised car count and the teams to get a guaranteed start and finishing position pay. These cars may start the race, complete a
Figure-8 Racing	Races run on a figure-8 shaped track. This is done by paving two lanes in an X shape through the infield of a conventional oval. In a Figure-8 race, there is an intersection in the middle of the track, which the cars must navigate to avoid wrecks with cr
Fill the Mirrors	When a driver is pressuring another driver so feverishly that the rear-view mirror is filled their pursuer.
Finish Line	Line, which determines winner and computes Elapsed Time.
Fire	When a tire gets up to temperature and begins gripping. May also be called
Fire Bottle	A brand name for a model of fire extinguisher designed to be used in a racecar; sometimes used to refer to a fire extinguisher in general.
Fire Suit	The suit worn by the driver (or others potentially exposed to fire, such as a gas man), consisting of several layers of a fire and heat-resistant fabric such as Nomex or Kevlar. The development of fire suits in the late '60s cut down greatly on burn injur
Fire Wall	A solid metal plate that separates the engine compartment from the driver's compartment of a racecar.
Fishtail	Aft lateral oscillation of a vehicle, generally the result of traction loss.
Flagman	Person who uses flags to signal various conditions to the drivers and teams. At weekly-racing events, the flagman is often the person who has the final say over the starting and stopping of the race, and handing out penalties to drivers who commit infract
Flags	Used by the flagman to signal various conditions to the drivers and teams. At most tracks, a series of signal lights around the perimeter of the track duplicates the functions of some of the flags.
Flag - Black	A flag demanding a car and driver report to the pits either because the team is to be penalized, or because the car presents some sort of hazard that must be fixed. A driver who continues after that point will be disqualified. At many tracks, an electric
Flag - Black and Red together	Flags indicating the end of a practice or qualifying session. All cars should exit the track and go to the pits or garage area.
Flag - Black with a White	Signals a racer that is ignoring a black flag that if he/she does not come in they will cease scoring that car.
Flag - Blue with Yellow stripe	A signal to lapped cars to move out of the way of faster cars. The actual rules associated with this flag vary considerably. In some series, a driver can be penalized for ignoring this flag; in others, it is strictly an advisory (and in fact, the flagman
Flag - Checkered (Black and White)	The race is over. This flag is always shown first to the winner; each car gets to complete the lap that it is on, and then the race ends.
Flag - Crossed flags	(two flags furled and crossed in an X shape): Indicates that half of the distance of the race has been completed. Usually, in oval-track racing, the rules stipulate that once one-half of the scheduled distance has been completed, if some condition (such a
Flag - Green and Yellow together	Used to indicate the start of a race, when it is necessary to start the race under caution. This might occur, for example, if it has rained before race time, the track is still damp, and the race needs to start by a certain time in order to meet televisio
Flag - Green	Start racing, or resumes racing. The green flag is waved at the start of the race, and at the end of every caution period; it remains out until the next caution period, or the end of the race.
Flag - Red	Race halted; all cars must drive slowly around to the start-finish line (or some other point designated by the officials) and then stop. Used when the track is blocked, or needs repair, or to signal a scheduled break in the race or when weather conditions
Flag - Red with Yellow "X"	Used by NASCAR to indicate that the pits are closed (in all of the NASCAR professional series, when a caution occurs, the pits are closed until the pace car has entered the track and the field is formed up behind it). An official positioned at the pit ent
Flag - White	One more lap remains in the race. In NASCAR, a car may not pit or receive any form of assistance (for instance, a push from another car) after taking the white flag.
Flag - Yellow	Caution period indicates that a wreck has occurred, or some other condition.
Flash Shield	A device to encompass the air inlet of a carburetor's sides, top, rear. To protect driver in case of engine backfire.
Flat	Description of a tire assembly that won't retain pressure.
Flat Out	To run a racecar at maximum speed.
Flat Spot	A portion of a tire worn down excessively due to locking the brakes or spinning the car.
Flip Ups	An aerodynamic device located in front of the rear wheels to direct airflow over the back tires.
Flopper	Slang term in drag racing to describe the Funny Car class. Derived from the fact that modern funny cars use a fiberglass body that "flops" down over the chassis.
Fly by Wire	A term, borrowed from aviation, to describe a control system where the driver, instead of directly controlling something through mechanical linkage, controls it indirectly through electrical actuators. In particular, refers to cars in which the steering,
Flywheel	A heavy metal rotating wheel that is part of the race car's clutch system, used to keep the crankshaft turning smoothly.
FMSA	Florida Mini-Sprint Association.
Footprint	The portion or amount of area of the tread that contacts the road.
Force Variation	A process to measure differences in tire/wheel consistency. Determines the highest portion of the tread in order to match it up to the lowest portion of the wheel for best performance and minimize tire/wheel assembly vibration.
Formula One	An open wheel series similar to Indy cars but with more sophisticated computer controls, higher rpm engines, and mostly run on road courses. Considered to be the highest form of motor sports.
Forward Bite	A general term used to describe the amount of force available to move the car forward. In setup, putting more forward bite in usually refers to adding more traction to the rear of the car.
Foul Start	Leaving the stage beam at the starting line before the green bulb illuminates resulting in immediate disqualification. Red lights at the bottom of the Christmas Tree signify a foul start.
Four-Barrel	The type of carburetor used in many types of racing.
Four-Link Suspension	Commonly used racing suspension. Found in all forms of racing, four link is characterized by four individual bars, two on each side of the rear end, used to control rear end movement and traction.
Four-Point, Five-Point	See harness.
Fours	Four-car-wide salute to the fans from the racers. Normally at the start of the night
FPRS	Formula Pro Racing Series.
Frame	The main structure or chassis of the car.
Frame Rails	Main lengthwise component beams of the chassis or frame.
Free	The same as loose. A handling condition (known as "over-steer" to road racers) where, when the car goes through a corner, the rear end of the car wants to slide towards the outside of the turn. If the car gets loose enough, it will spin out. Adjustments c
Freight Train	A group of drafting cars lined up like a train.
Fresh Rubber	New tires.
Friction	Contact between two surfaces. Usually results in heat.
Front Clip	Beginning at the firewall, the front most section of a racecar.
Front Steer	An arrangement of the steering gear where the tie rods connect to the wheel hub at a point forward of the kingpin.
Front Stretch	Main straightaway between turns 4 and 1 on an oval track.
FSCDRS	Fastest Street Car Drag Racing Series.
Fuel	Flammable liquid used to power internal-combustion engines.
Fuel Cell	A type of fuel tank that has a rubber (or similar) inner lining, to contain the fuel if the outer tank is punctured. Most also contain a foam or metal-mesh filling, which prevents fuel sloshing and keeps the flame out of the tank if a fire occurs.
Fuel Check	An area of technical inspection in which fuel is tested for compliance.
Fuel Injection	(F.I.) A system replacing conventional carburetion, which delivers fuel under pressure directly into the combustion chamber.
Fuel Pump	A device that pumps fuel from the fuel cell through the fuel line into the carburetor.
Fuel Stint	The amount of laps or time run on a full tank of fuel.
Full Bore	Running as fast as possible.
Full-Face	A helmet that covers the entire face and head. When used with a head sock, it provides full-uninterrupted coverage of the driver's upper body against fire, and the enclosure of the mouth prevents the driver from inhaling the flame during a fire. It also p
Full Floater	A type of rear axle where the axle housing extends all the way out to the wheels, and the wheels are held on bearings fastened to the ends of the housing tubes. Works in conjunction with drive plates.
Full Tree	The method used to start cars at the starting line. The method used is one yellow light is used at a time, then the green light. As opposed to all yellow lights are lit at once then the green light (Pro-Tree). The reaction time used in full tree is .500.
G	Gravitational forces exerted on a car and driver under acceleration, braking, and cornering.
Garage Area	A covered or enclosed area, usually in the infield of an oval track, where the racecars are stored and worked in when not on the track. The garage area is the place for performing repairs that are more extensive than possible in the pits. The garage area
GARRA	(Grand Am) Grand American Road Racing Association. Sanctions Sports Car racing events in the US and Canada.
Gas	Used to mean gasoline (as opposed to alcohol or other fuels). This usage appears more commonly in drag racing, where a division with the word "Gas" in its name means those cars in that division must run on gasoline, but it is also used some in oval track
Gas Catcher	Pit crewmember that is responsible for the catch can. This person may also perform other duties during a pit stop.
Gasket	A thin material, made of paper, metal, silicone, or other synthetic materials, used as a seal between two similar machined metal surfaces such as cylinder heads and the engine block.
Gasman	The member of the pit crew who refuels the car. In stock car racing this person must lift heavy cans of racing gasoline (Usually 22 gallons weighing about 87 lbs. or 40 kg) up to the car's filler inlet. In Indy car racing, this person handles a large hose
Gasoline	see gas:
Gasoline Alley	The garage area at Indianapolis Motor Speedway.
Gasser	A dragster or any car that runs on gas.
Gather/Gathered It Up	Regaining control of a racecar after becoming loose or spinning.
Gathered Up	A car becoming involved in a wreck not his/her fault. Being
Gauge	An instrument, usually mounted on the dashboard, used to monitor engine conditions such as fuel pressure, oil pressure and temperature, water pressure and temperature, and RPM (revolutions per minute).
GCS	Golden State Challenge.
Gearbox	Racing term for a transmission.
Gear Ratio	The ratio of engine RPM
Gears	Circular, wheel-shaped parts with teeth along the edges. The interlocking of two of these mechanisms enables one to turn the other.
Gearset	Two or more gears used to transmit power.
Gilmer Belt	Toothed or splined drive belt used with matching pulley, generally a non-slip drive belt. The large belt used to transfer power from the engine's crankshaft to the input shaft of a supercharger. Most are reinforced and molded to match the teeth of the dr
Give Up	Gradual or drastic deterioration of a tires performance during use.
Glass Transition Point	The temperature that the tread rubber will freeze and crack. This temperature will vary depending on the rubber compound.
GLOSS	Great Lakes Outlaw Sprint Car Series.
Going up through the Gears	Refers to a driver up-shifting from the lowest to the highest gear.
Gold Crown	The name that USAC used for its Indy car series between about 1970 and 1980. Prior to about 1970 there were few paved-track Indy car races; many races which were part of the "National Championship Trail" (which traces its lineage back to the AAA days) wer
Got Under	When a car out brakes another going into a turn and passes on the inside.
Graining	A pattern of nearly parallel ridges on a tires tread. Cause by over aggressive driving on a tire that has a compound that is usually too soft or has not been allowed to be brought up to a good operating temperature.
Grand Am	Grand American Road Racing Association. Sanctions Sports Car racing events in the US and Canada.
Grand Marshal	An honorarium, usually reserved for sponsors and celebrities. Feature races often have a grand marshal, whose most visible function is doing the traditional "Gentlemen, start your engines" bit at the beginning of the race.
Grand National	The original name for what is now known as the NASCAR Winston Cup series. The Grand National name was adopted in the early '50s, and persisted until 1971 when the series named was changed to Winston Cup, after its title sponsor. To make things confusing f
Grand National East	This was a series created by NASCAR in 1972. It consisted of all of the dirt-track races which were removed from the Winston Cup series that year, both to reduce the number of races on the WC schedule and because the dirt races were considered old-fashion
Grand National West	At the time that NASCAR created the Late Model Sportsmen championship for local and regional racers in the South and East in 1948, it recognized that it would be impractical for teams on the West Coast to tow their cars to the other side of the country to
Grand Prix	This French term meaning grand prize is widely used to refer to a race. At one time in racing, it was used exclusively for a series' grand finale, usually the most important race.
Gray	Area on a paved track where nobody runs, particular in the corners. Sometimes it actually is visibly a lighter color than the groove. The gray area is often full of marbles and other loose material that causes a severe loss of traction for any car that go
Green	(1) The state of the track when a green flag is in effect; the opposite of a caution period. (2) A track which is either newly paved, or has experienced heavy rain since the last time the track was raced on, or just hasn't been used in a while. A "green"
Green and Yellow Flags together	Used to indicate the start of a race, when it is necessary to start the race under caution. This might occur, for example, if it has rained before race time, the track is still damp, and the race needs to start by a certain time in order to meet televisio
Green Flag	Start racing, or resumes racing. The green flag is waved at the start of the race, and at the end of every caution period; it remains out until the next caution period, or the end of the race.
Greenhouse	The area inside the racecar, generally referring to the top inside part of the racecar, where the driver sits. The greenhouse area is basically from the windshield to the back deck lid, and from the doorframes up.
Green Tire	A completely assembled tire that has not yet been cured. Also refers to an environmentally friendly tire that uses less oil.
Green Track	A track which is either newly paved, or has experienced heavy rain since the last time the track was raced on, or just hasn't been used in a while. A "green" track lacks the accumulation of tire rubber that builds up when the track is raced on, which chan
Green/White/Checkered	When a caution occurs near the end of a race, the series officials may choose to go passed the advertised race length to get the race in under green. They may finish the caution and then go green for one lap, followed by the white flag indicting one lap t
Grenade	An engine built to go very fast for a few laps, for qualifying. Grenade engines are usually built with lightweight parts and will often blow in spectacular fashion if run for more than a handful of laps.
Grid	The starting order of the field, in the physical positions that they will actually start the race. Also refers to the part of the track where cars are assembled pre-race.
Groove	(1) The line or path through a corner which drivers have found to be the fastest. Where the groove is depends on a huge number of factors, such as the type of paving, the car weight, tires, downforce, driving style, track and weather conditions, etc. It i
Grooving	A term used when a tool with a blade is used to alter the tread pattern of a tire. When using this tool it will create a new groove in the tread surface. The size of the groove varies and depends upon the width of the blade being used. This method is used
Ground Effects	Use of airflow under the car to create downforce. (The term "ground effects" comes from aviation, but there it means the opposite: the tendency of an airplane near the ground to float on a high-pressure cushion of air.) Most ground effect cars use passive
Growing	In racing, when tire circumference increases as speeds increase. Tire growth is important in heads-up classes where speed determines the race outcome. Less contact patch on the top end leads to more M.P.H. In oval track racing, when the circumference of a
GTA	GT American Road Racing Association.
Guard Beam	Light beam positioned 16 inches ahead of the stage beam to prevent racers from using side panels behind the front tires to block the staging beams, thereby gaining a starting line advantage. If the guard beam is reached before the car leaves the staging b
Gurney Flap	A small spoiler-like tab that sticks up (or down) perpendicular to an aerodynamic surface, such as a wing; it has the effect of increasing air pressure on that side of the surface, making it produce more force in one direction or the other. Perfected in t
Gusset	A reinforcement addition adding web-like or triangulation reinforcement to car structure, usually welded in place.
Hairpin	A slow, tight 180-turn which exits in the opposite direction a driver enters.
Half-Shaft	In a car with independent suspension on the rear wheels, the part that carries the engine power from the rear end to the wheels. (Or the front wheels on a front-wheel-drive car.) The half shaft must have some kind of mechanism in order to be able to move
Halftime	A scheduled break in a race that occurs when half of the scheduled laps have been completed. A red flag is flown, and all cars go to the pits for 5-10 minutes, where work can be done. The halftime is used when a racing series wants to de-emphasize the imp
Halon	Special Freon Fire Extinguisher. Generally a 3% to 5% concentration will extinguish fire.
Hammer Down	The driver has the gas pedal "to the metal"- full throttle.
Handicap	In bracket racing, when one car is faster than the other, the slower gets a head start. Handicaps are based on previous elapsed times or dial-ins.
Handling	A general term for the racecar's capability to go where the driver wants it to go on the track, and be fast in the process. See loose and push.
Hanford Device	A type of rear wing used by CART on superspeedways. The Hanford device is intentionally designed to produce very high aerodynamic drag, in an effort to slow down the extremely fast CART cars on superspeedways. Results have been mixed; the racing that resu
HANS Device	Head and Neck Restraint System. A driver restraining system that straps over the driver shoulder and securely attaches the helmet to anchors to reduce the snapping motion of the driver's neck during an impact.
Happy Hour	The final hour of practice before an event, usually held the day before the race day and after all qualifying sessions and support races have been staged.
Hard Charger	The driver that has passed the most cars in the race.
Harmonic Balancer	An element used to reduce vibration in the crankshaft.
Harness	The safety belt system worn by a race driver. The basic racing harness is a "four-point" unit; it has four belt lengths that meet in the middle of the driver's pelvis. Two points form a conventional lap belt, same as in a passenger car; the other two go u
Hat Dance	A routine performed by the winning driver where he is photograph in victory lane with each of the sponsors and sanctioning bodies hats.
Hauling The Mail	A term used by drivers to describe going really fast.
Head Sock	A fireproof hood that covers the entire face (except eyeholes), head, and neck. Usually worn under a full-face helmet. Also referred to as a "balaclava".
Head Wrench	Slang term for a race team's crew chief.
Headers	Fine-tuned tubular exhaust system routing exhaust from engine. Replaces conventional cast exhaust manifolds.
Heads Up Race	In drag racing, when two cars from the same classification in stock and super stock meet in an elimination round.
Heat Cycle	Refers to the number of times a tire is run up to operating temperature and then allowed to fully cool.
Heat Race	A preliminary race to a feature. Heat races are generally short, 8-15 laps in distance. They serve to get both the cars and the fans warmed up for the feature, and sometimes the outcome of the heat races is used to determine the starting order of the feat
Heel	The area of the bead that describes to transition radius between the vertical and horizontal surfaces.
Heel and Toe	When a driver uses his right foot to operate both the accelerator and brake pedals. Used on tracks that demand a lot of shifting.
Hemi	(1) A type of cylinder head where the combustion chamber is roughly in the shape of a hemisphere. Generally the valves are opposite each other on the dome of the head, with the spark plug centered; this results in better breathing and ignition characteris
Hides	Slang term for tires.
High and Dry	When a racecar becomes too high on the track and loses one or more positions.
High-Centered	To get a car hung up on a curb in a "see-saw" position so that neither the front nor the rear wheels has traction. (This is easy to do with racecars, which generally have little ground clearance.) The car can't move until it is pushed off the curb.
High Groove	The line or path on the track nearest to the outer wall. Where the groove is depends on a huge number of factors, such as the type of paving, the car weight, tires, downforce, driving style, track and weather conditions, etc. It is not uncommon for the gr
High Heat	Describes over heating of a tire usually 260 degrees or hotter.
Hitting Your Marks	The best spots on the track to either get on or off the throttle. Also may refer to the best line or spots on the track in which to run.
Hobby	A general name for a beginner-level Stock car class or division. Also sometimes referred to by names such as Rookie, Street, Cadet, etc. Hobby classes are usually based on older-model sedan bodies (the early '70s Chevelle/Impala is common), and engines wi
Hole Shot	A drag racing term for beating an opponent off the starting line and winning a race despite having a slower elapsed time. Other racers use this term to describe a good start or restart.
Hood	Panel that protects and allows access to the engine.
Hood Pins	Metal and wire tethers used to secure the hood.
Hooked Up	A car that is performing great because all parts are working well together.
Horsepower	Used to measure the strength of any engine or motor. One horsepower equals 33,000 foot-pounds per minute or the force needed to lift 33,000 pounds at one foot per minute.
HOSS	Hoosier Outlaw Sprint Series.
Hot (track or pits)	The condition of the track and pits when racecars are on the track (whether at speed or not). For safety reasons, tracks have restrictions on who can be in the pits or garage area when the track is hot.
Hot Lap	Running at race speed or near race speed during practice or testing.
Hot Shoe	Slang term for a fast driver.
HSCRA	Historic Stock Car Racing Association.
Hub	The part that connects the axle to the wheel.
Humpy's House	The Charlotte (Lowe
Hundredths	1/100th of a second. Used in timing lap times. The second digit to the right of the decimal point.
Hunting the Bottom	Slang term for a racecars ability to cut into the turn well and stay on the bottom of a corner.
Hutchens Device	Driver's head and neck restraint system.
Hydraulic	When a cylinder fills with too much fuel, thus prohibiting compression and causing a mechanical malfunction, usually an explosive one. Most often seen in Nitro-methane-powered classes such as Top Fuel and Funny Car.
Hydroplaning	A skimming effect caused by tires losing contact with a surface covered with water.
Hysteresis	The rate that a rubber compound bounces back to its original shape after pressure has been applied.
IDBA	International Drag Bike Association.
Idiot Light	Can refer to a light that alerts the driver to a malfunction (as in a passenger car), but in a racing context, it usually refers to a large, attention-getting light that alerts the driver that the brake and/or clutch pedal is being depressed. Such a thing
Ignition	An electrical system used to ignite the air-fuel mixture in an internal combustion engine.
IHRA	International Hot Rod Association.
ILMS	Intermountain Late Model Series.
IMCA	International Motor Contest Association. Probably the oldest existing sanctioning body in the world, IMCA has been sanctioning Modified and Stock car racing, mostly on dirt, in the U.S. Midwest and West since the '30s. In the '90s, IMCA experienced a surg
Impact Wrench	A powered wrench that uses a combination of torque and a hammering action to loosen and tighten fasteners. Racers often use this term (improperly) as a synonym for air wrench.
IMS	Intermountain Mini-Sprints.
IMSA	International Motor Sport Association, the former name of the sanctioning body now known as Grand American Road Racing. This body was formed in the early '70s to sanction professional sports car racing in the U.S. IMSA sanctions the 24 Hours of Daytona.
IMTRA	International Mini-Truck Racing Association.
In Contention	In general, describes a car that has a legitimate shot at a race victory.
Inboard Brakes	Refers to the mounting of a car's braking mechanism inside the car body, rather than on the wheel as is usually done. The advantage of inboard brakes is that they reduce the wheels' un-sprung weight, which improves handling.
Increasing Radius Corner	A turn that has a smaller radius during the first half of the corner.
Independent	A driver who owns his own racing team, and relies on race winnings as much or more than sponsorship money to finance his racing.
Independent Suspension	A type of suspension where an axle does not support connecting wheels, but by suspension members that support each wheel separately.
Index	1) Elapsed time assigned by a sanctioning body such as NHRA or IHRA that defines a class (8.90 is the standard index for Super Comp in NHRA). Index may be altitude adjusted. 2) An index also allows various classes to race together with an equitable handic
Index Finger	When shown during a caution period, indicates that one lap under yellow remains, and that the green will be waved on the next lap. This is also indicated by the pace car turning off its flashing lights.
Indy Cars	An open wheel formula using small-displacement, methanol- burning, engines. Named after the Indianapolis Motor Speedway, where they have raced since 1909, Indy cars are the only American oval-track racing types that have been heavily influenced by direct
Indy Racing League (IRL)	A sanctioning body, owned and run by Indianapolis Motor Speedway president Tony George. The IRL conducts a series of Indy car style racing using cars that resemble (but are less expensive than) cars as sanctioned by CART. The IRL runs exclusively on ovals
Infield	The area enclosed by the racecourse. Typically, the infield contains the pits, the garage area (if there is one), and spectator areas (at most larger tracks). Some large oval tracks have road courses running through their infields. However, at some short
Inline	Commonly used to describe an engine with all cylinders and valve stems in a single row.
Inner Liner	A safety device for racing tires. An inner liner is a sort of tire-within-a-tire; it has its own air containment and its own valve stem separate from the main carcass of the tire. The inner liner is inflated to a pressure higher (usually 12-15 psi) than t
In/Out Box	Contains direct drive slider gears on a Sprint Car. Since Sprint Cars do not have a clutch, the car has to be put in gear to be ready to race.
Inside Line	The shortest line around the track. Also, the part of the track that is closest to the infield.
Inspection	A specific set of guidelines set by the race officials that all competitors must adhere to. Generally, there are two main categories of inspection, safety and rules inspection. Seats, harnesses, brakes, and steering are usually safety inspections while en
Intake Manifold	A housing that directs the air/fuel mixture through the port openings in the cylinder heads.
Intermediate	A tire that is intended for use in damp or slight rain conditions.
Intermediate Track	A racetrack that is usually more than one mile but less than 2 miles in length.
Interval	The time-distance between two cars. Referred to roughly in car lengths, or precisely in seconds.
Interval Timers	In drag racing, interval timers are part of a secondary timing system that records elapsed times, primarily for the racers' benefit, at 60, 330, 660, and 1000 feet.
Inverted Start	A starting order where the first qualifier starts last, the second qualifier starts next-to-last, and so on. Most often seen in asphalt short track racing to increase competition and further entertain spectators.
IRA	International Racing Association or Interstate Racing Association.
IRL	Indy Racing League. A sanctioning body, owned and run by Indianapolis Motor Speedway president Tony George. The IRL conducts a series of Indy car style racing using cars that resemble (but are less expensive than) cars as sanctioned by CART. The IRL runs
IROC	International Race of Champions. Sanctions like prepared cars and features selected drivers from different forms of racing.
ISA	International Stock Car Association.
ISMA	International Super Modified Association. Sanctions Super Modified racing in the United States and Canada.
Jack Man	The member of a pit crew who operates the jack.
Jack Post	Sturdy post or rail on the side of the car where the jack man places the jack.
Jericho	A type of manual transmission, designed so that most gearshifts can be accomplished without using the clutch (except for shifting into gear from a dead stop). It accomplishes this trick using "dog-ring" shifters and straight-cut gears that can be mated at
Jet	When air is sent at a high velocity through the carburetor, jets direct the fuel into the airstream. Jets are made slightly larger to make a richer mixture or slightly smaller to make a more lean mixture, depending on track and weather conditions.
Jumping The Start	When a driver anticipates the start (green flag) too early. This will cause a complete restart. Continued violations will result in a penalty.
Junior Dragster	An entry-level class for children under age 16 in NHRA drag racing competition. Junior Dragsters are
Junior Fuel	A class of drag racing that reflects the history of today's Top Fuel Class. Jr. Fuel cars look and perform like Top Fuel cars of the 60's. Traditional front-engine dragsters are combined with smaller engines, narrow tires, and restricted Nitro-methane fue
KARS	Keystone Auto Racing on Speedways.
Kart	A very small, open-frame (no bodywork) single-seat car powered by a low-displacement engine similar to (but more powerful than) a lawnmower engine. Karts generally are direct drive with no transmission (although there are "shifter karts" which have gearbo
Kevlar	A high stiffness, high strength material developed by DuPont. Used as tire cord because of its good mechanical and chemical properties at high temperature.
Kilopascal	(kPa) The metric unit for air pressure. There are 6.9 kPa's to one psi.
Kitty Litter	Slang term for Speedy Dry or other granular substances used to soak up oil, gas, or water spills.
KLASCAR	Keystone Legends Association of Stock Car Auto Racers.
Ladder Bars	A 3-point traction device with 2 attaching points at rear axle housing and 1 point at frame. Used to transfer traction back to rear wheels by changing pinion angle and preventing excess rear weight transfer.
Lap	One complete circuit around the track.
Lapped Car	A car, which is running, slows enough (or been in the pits long enough), such that the race leader has come all the way around the track and passed it, has been "lapped". This means that it has run at least one less lap than the leader.
Lapped Traffic	Cars that have completed at least one full lap less than the race leader.
Late Apex	Turning into a corner late and missing the optimum apex point.
Late Model	A general name for an advanced-level Stock car class or division. These cars usually have purpose-built tube-frame chassis.
Lateral G's	Sideway force experienced while turning.
Lay Down Engine	All V-shaped engines are top-heavy. In the mid'50s (back when Indy cars were still front-engine), some chassis designers figured out that by tipping the engine on its left side, the engine could be made lower in profile. This placed its center of gravity
Lead Lap	The lap that the race leader is currently on.
Lead Foot	Slang term for a driver who is very fast, but is also rough on equipment and doesn't know when to take it easy. Lead foot drivers win many races, but they also break cars and crash a lot.
Lean	Running and lower fuel to air mixture. Drivers trying to conserve fuel will "run their engines lean" by using a decreased fuel/increased air mixture.
Left Foot Braking	A technique used on oval tracks where shifting gears at speed is not necessary. Braking with the left foot provides shorter reaction time, since the foot does not have to be moved from one pedal to the other. However, the driver must be careful not to "ri
Legends	A Dwarf car, spec series promoted by Charlotte Motor Speedway owner Humpy Wheeler. Legends cars are built to tight specifications exclusively by 600 Racing. A sealed, 4-cylinder Yamaha motorcycle engine powers them, and no modifications are allowed to any
LeMans Start	A type of race start where the drivers are outside of their cars, given a signal, then they must run to their cars, start the engines, and begin racing.
Let Go	Term to describe when an engine fails or "blows up." Also when other parts of a car fail.
Lexan	A trade name of General Electric used for a durable thermal resistant plastic material used where transparent material is required (i.e.. face plates, goggles, windows, etc.):
Lift	To let off or
Lights Out	When the lights on the pace car, emergency vehicles, and track lights go out. Usually when the starter is ready to display a green flag during the last lap before the start or restart.
LIMCA	Long Island Mini-Cup Association.
Limited	A general name for an intermediate-level Stock car class or division. These cars are more advanced than Street or Hobby cars; often they will be later-model bodies (some tracks permit drop-on one-piece plastic bodies in this class), and purpose-built chas
Line	(1) The route taken by a driver, especially through a turn. The high line is a route close to the wall. A low line is closer to the track's infield and shortest distance around the track. (2) The painted line at the inside of the track usually considered
Linear Spring	A spring that compresses at a steady rate. For example, 1-inch of deflection for each 200 pounds applied. See Progressive spring.
Little Car	Encompasses a wide range of competition, which includes Mini-Champs, TQ
LMTRA	Late Model Truck Racing Association.
Load Index	An assigned number ranging from 0 to 279 that corresponds to the load carrying capacity of a tire.
Load Range	DOT required specification. Calculation based on pressure, construction and speed. The average load a tire can bear without damage under set specifications.
Loaded Section Height	The height of the section of the tire that is making contact with the road.
Lock Down	To apply the brakes hard enough to totally lock the wheels during a spin. When a car's brakes are locked and all four wheels are sliding, the car will keep going in whatever direction it is currently going, regardless of which way the front end points.
Locked Rear End	Normal rear-end gears in a rear-wheel-drive automobile perform a "differential" function; when the car goes around a corner, they permit one wheel to turn faster than the other, to compensate for the fact that the wheel on the outside must cover a greater
Long Block	Refers to a stage of assembly of an engine (and the state of assembly that engines might be sold in). Engine assembly ranges from "bare block", which is just an engine block with no moving parts, to "short block", which is a block with crankshaft, rods, a
Long Pedal	Commonly refers to a car's gas pedal because of the design. Also used to describe a brake pedal when brakes wear out because the driver has to push the pedal harder and further to slow down.
Loose	A handling condition (known as "over-steer" to road racers) where, when the car goes through a corner, the rear end of the car wants to slide towards the outside of the turn. If the car gets loose enough, it will spin out. Loose is the opposite of push an
Loud Pedal	The accelerator, gas pedal, or throttle.
Low Groove	The line or path on the track nearest to the infield. This is the shortest distance around the track but in some conditions it may not be the fastest. Where the groove is depends on a huge number of factors, such as the type of paving, the car weight, tir
Lug Nuts	Threaded nut that when screwed onto the lugs, attaches the wheel to hub.
Lugs	1) Threaded stem or bolts that connects the wheel to the hub with lug nuts. 2) Large rubber blocks in the design of a tire tread.
MACS	Mid-Atlantic Championship Series.
MAFCC	Mid-America Funny Car Circuit.
Magnaflux	The process of using a special electromagnet and magnetic powder to detect cracks in iron, which may be invisible to the naked eye. Used to check chassis and engine components to detect potential problems before they occur. MANDRA Mid-Atlantic Nostalgia
MARA	Midwest Auto Racing Association.
Marbles	Loose pieces of rubber or debris above the upper groove on the racetrack.
MARS	Mid-American Racing Series or Midwest All-Star Racing Series.
Maximum Inflation Pressure	The maximum air pressure to which a cold tire may be inflated; found molded onto the sidewall or specified by a tire manufacturer.
MCR	Midwest Classic Racers.
MCSCC	Midwest Council of Sports Car Clubs.
MDRA	Midwest Drag Racing Association.
Meats	Slang term for tires. Mostly used in drag racing.
Memory Tach	A tachometer, which records its RPM readout over the course of a lap, or a few laps, and can replay the readout on command. Memory tachs are useful for diagnosing things like wheel spin coming out of a corner and some have features such the ability to dis
Methanol	Technically pure methyl alcohol CH3oh (toxic) produced by synthesis.
Micro-Sprint	Form of racing using
Midget	An open wheel car formula using short wheelbase chassis with driver enclosed in a roll cage and the engine in front of the driver. Midget cars run on ovals exclusively. Engines are usually 4-cylinder, normally aspirated. At one time, outboard (boat) motor
M.I.G.	Metal Insert Gas Arc welding. Uses a continuous-feed filler rod material pulled through the torch from a roll of wire.
Mini-Sprint	Form of racing using
Mini Stock	A general name for a class or division based on '70s or '80s compact-car models such as the Ford Mustang, Pinto, and Pontiac Sunbird. These are characterized by lightweights and 4-cylinder engines, with the level of rules and competition being otherwise s
Minimum Weight	The lowest allowed weight for the vehicle in its class. Can be measured pre or post race.
Mirror Driving	Driving while paying an inordinate amount of attention to a car or cars behind (while paying less attention to one's own line); especially, driving so as to make it difficult for faster cars behind to pass. Usually considered poor form.
MLRA	Midwest Late Model Racing Association.
MMA	Michigan Modified Association.
MMRA	Miniature Motorsports Racing Association.
MNMRA	National Motorsports Racing Association.
MNNA	National Modified Midget Association.
Modified Midget	Form of racing using
Modifieds	These are open-wheel, enclosed-cockpit, front-engine cars that race mainly on ovals. Some have external framing, often known as "nerf bars", to add chassis stiffness, and to protect the front end and sides of the car. There are a number of formulas, rangi
Modulus	A measurement of a given materials stiffness and how much it deforms in response to stress. Usually referring to rubber.
Moonpie	Slang term for a serious, dedicated, and very excitable race fan.
Mount	Installing a tire on a rim or wheel.
MOVRC	Midwest Old-timers Vintage Club.
MPH.	Miles per hour.
MPSA	Midwest Pro Stock Association.
MRA	Midwest Super-modified Association.
MSCS	Midwest Sprint Car Series or Midwest Super Comp Series.
MSRA	Modified Stock Racing Association.
MST	Montana Sprint Tour.
MVRCA	Maine Vintage Racing Car Association.
MVSCC	Mid-state Vintage Stock Car Club.
NAMARS	North American Auto Racing Series:
NAMRA	North American Mini-Champ Racing Association.
NASA	National Auto Sport Association sanctions road racing.
NASCAR	National Association for Stock Car Auto Racing. The top promoter of stock car racing in the U.S., NASCAR sanctions series ranging from the Winston Cup series, through regional racing in the South, Southwest, and Northeast (U.S.), down to local Saturday ni
NBS	NASCAR Busch Series.
NCMA	Northern California Modified Association.
NCRA	National Championship Racing Association.
NCS	Nextel Cup Series.
NCTR	National Dirt Truck Racing.
NCTS	NASCAR Craftsman Truck Series.
NEAR	New England Antique Racers.
NEMA	Northeastern Midget Association.
NESCC	New England Sprint Car Club.
Neutral	(1) A position of transmission in which the engine and the drive train are not engaged. (2) A term driver's use when referring to how their car is handling when a car is neither loose nor pushing tight.
NFCA	Northeast Funny Car Association.
NHRA	National Hot Rod Association sanctions national drag racing events.
Nitro	Short for nitro methane, an oxygen-containing exotic fuel. Mix ratios are generally 90% methanol to 10% Nitro-methane.
Nitrous	Short for nitrous oxide (N2O), the same stuff that the dentist puts you to sleep with. When injected into an internal-combustion engine, it provides extra oxygen (being about 35% oxygen, as opposed to air, which is 21% oxygen), and gives the engine a boos
NLMSS	National Late Model Series, Southern Dirt Tour:
NLRA	Northern Late Model Racing Association
NMCA	National Mustang Racing Association:
NMMA	National Modified Midget Association. Sanctions modified midget racing in the United States.
NMRA	National 3/4 Midget Racing Association and Ford Racing Series
NNCS	NASCAR Nextel Cup Series.
Nomex	A trademark for a fire-resistant fiber often used in fire suits. Originally invented by Du Pont for NASA in the early '60s, Nomex was introduced to racing in 1970, and has enormously improved the safety of the sport. There are now other fibers around that
Nominal Rim Diameter	The diameter of a tire rim, given in nearest whole numbers (e.g. 15"):
Non-Fill	Small portions of the tire that did no completely fill in during expansion in the tire press. Cosmetic in nature and most often occur on sidewalls of tires.
Normally Aspirated	Term for an engine that does not employ turbo charging or supercharging. Most Stock, Midget, and Sprint car racing engines are normally aspirated. IRL mandated normally aspirated engines in its Indy car series starting in 1997.
NOS	(1) Abbreviation for New, Old Stock. Refers to new but older products or replacement parts. (2) Abbreviation for Nitrous Oxide Systems.
Nosing Over	When a racecar's performance "flattens out" or doesn't pull down the straights anymore. Poor tuning or exceeding the engine's power range cause this.
Nose Wing	An airfoil, used to generate down force to improve steering capabilities. It is normally around 3' x 2' in size. The wing is usually mounted directly above the front axle.
Novelty Racing	A form of racing, which relies on a trick or gimmick to make it appealing to the fans.
NORA	Northeast Organized Racing Association.
NOSA	Northern Outlaw Sprint Association and Sprint Invaders.
NSCA	Nebraska Sprint Car Association.
NSRA	Northwest Sprint Car Racing Association.
NSS	Nostalgia Super Stocks.
NST	Northern Sprint Tour.
NVRA	National Vintage Racing Association. Sanctions vintage oval track racing.
NWCS	NASCAR Winston Cup Series.
NWMS	Northwest Modified Series.
NWSST	Northwest Street Stock Tour.
OCRS	Oil Capital Racing Association.
O.E.	Original Equipment (as originally produced and installed by factory that manufactured automobile.) Originally equipped.
O.E.M.	Original Equipment Manufacturer. Original Automobile Manufacturer.
O.H.C.	Overhead Cam.
Off-Camber Turn	A corner with negative banking (the inside edge of the corner is higher than the outside edge). Seldom if ever seen on ovals, but some road courses have them.
Off-Road	(1) A form of racing which runs on an unpaved, ungraded course. Traditionally, this is a point-to-point, natural-terrain open course (for example, the Baja 1000). But, as environmental concerns have restricted the use of natural-terrain courses, forms of
Offset	(1) Weight: The difference in weight between the left and ride sides of the car. On an oval track, handling is improved by having as much weight over to the left as possible, so car builders usually offset the weight to the left as much as the series rule
Oil	Liquid use to lubricate mechanical parts.
Oil Pump	A device that distributes oil throughout the engine to lubricate all moving parts.
On the Bubble	The last position available to qualify for the race.
One-more-lap Signal	A signal to the drivers that the green flag will be flown on the next lap. This usually consists of two things: the flagman holding up one finger, or a furled flag in the shape of a one, to the field and the pace car turning its flashing lights off.
Open Competition	A series or event in which there are no specific rules governing the use of a
Open Hand	Indicates that five laps remain in the race.
Open Wheel	Cars that have their wheels exposed with no fenders such as Sprint Cars and Midgets.
Opposite Lock	A technique for taking corners on a dirt track (particularly one where the surface is loose or muddy). This involves turning the car left into the corner and accelerating to make the rear end slide out. The wheel is then turned right all the way to the st
Option Tire	An alternate tire made available by a tire manufacturer for a particular race. Often the option tire is made from a softer compound, which means that it will generally be faster but will not last as long and may be prone to blistering. IRL permits tire ma
OSCA	Outlaw Street Car Association.
OSCAAR	Ontario Stock Car Association of Asphalt Racing.
Otto Cycle	The four operations of intake, compression, power, and exhaust that constitute one revolution of a cylinder in a 4-cycle engine. Also called a cycle. Named for inventor Dr. Nikolaus Otto.
Out Brake	A driver gains time and position on an opponent by applying the brakes later and deeper into a corner.
Outlaw	A race run without the supervision of a sanctioning body, or a track that runs such races. In an outlaw race, the promoter or track owner usually does the job of forming and enforcing the rules. The term goes back to the '40s and '50s, when sanctioning bo
Oval	In general, a somewhat circular racecourse containing only left-hand or right-hand turns. The actual shape of the track is often not, strictly speaking, oval: other shapes include Tri-oval, Quad-oval, D-oval, Rectangle, and Triangle. (See individual defin
Overall Diameter	The diameter of the inflated tire, without any load.
Overall Width	The distance between the outside of the two sidewalls, including lettering and designs. Also known as section width.
Overflow	Usually refers to the line from the radiator cap's relief valve. On a passenger car, this goes to a catch bottle, but on a racecar, it is usually allowed to vent. Some Stock cars bring the vent line out from under the hood cowl, so that escaping steam or
Overhead Cam	An engine having the camshafts positioned atop the cylinder heads, as opposed to a pushrod engine (see). These fall into two classes: Dual-overhead- cam (DOHC) designs have two camshafts over each bank of cylinders; generally one cam operates the intake v
Overhead Valve	An engine having the valves in the cylinder head, above the top of the piston. In the early days of internal-combustion engines, most engines were "flathead" engines, where the cylinder head was simply a flat plate (with holes drilled for the spark plugs)
Oversteer	A handling condition (known as "loose") where, when the car goes through a corner, the rear end of the car wants to slide towards the outside of the turn. If the car gets loose enough, it will spin out. Oversteer is the opposite of push and under-steer.
Pace Car	A car, which comes onto the track, in front of the race leader, and leads the field whenever a caution flag is in effect. The pace car has two important functions: setting the permissible speed during yellow flag periods, and gradually bringing the field
Pace Lap	A lap just before the start of a race, where the pace car gradually brings the field up to racing speed. The purpose of the pace lap is to prevent big discrepancies in speed between different cars from developing; having all cars start the race at nearly
Pacer Light	At one time, Indy car racing had a rule, on oval tracks that required cars to maintain their separation during a caution period, rather than bunching up behind the pace car. The pacer lights were a set of sequenced signal lights around the periphery that
Paddock	A road racer's term for what oval-track racers call the garage area. Sometimes, however, the "paddock" does not actually contain garages, but is simply an open area away from the racing surface, where cars can be worked on.
Panhard Bar	In a rear suspension, a lateral bar that prevents the axle from moving left or right. It is generally attached to the end of the axle housing on the left, and to a frame bracket on the right. Also called a track bar.
Parade Lap	The first lap taken by the field as the cars get under way, before the start of the race. The parade lap is run at a very slow speed. Its purpose is mainly ceremonial.
PASS	Pro All Star Series.
PCDLMT	Pacific Coast Dirt Late Model Tour.
Penalty Box	A NASCAR term for the assessment of a five-lap penalty, which is NASCAR's most stringent during-race penalty short of disqualification. Imposed for severe infractions, such as intentionally spinning or wrecking another car.
Penalty Spoiler	A spoiler, which is affixed by the officials to a car to make it slower (as opposed to the usual purpose of a spoiler). Penalty spoilers are sometimes used to equalize cars, which have illegal bodywork, allowing them to compete without the team having to
Photo Finish	Means the same thing that it does in horse racing: a finish that is so close that a photograph, taken at the moment of finish, must be examined in order to determine the winner. (Recently, high-speed video camera systems have been replacing photography fo
Pick	Refers to when a car is trying to pass another car, the car under attack may pass closely by a slower car, such that the slower car is on the same side as the attacking car. The attacking car then has to back off, and get in line with the lead car in orde
Pick Up	Debris built up on the tires consisting of rubber bits or stones.
Pilot Chute	In drag racing, a spring-loaded device that pulls out the braking chutes from its pack.
Pinched	When a racecar squeezes another car into the inside or outside wall.
Piston	A round metal cylinder, which is attached to the top end of the connecting rod inside of the cylinder. The piston compresses the air/fuel mixture on the upward motion, and is pushed downward when the air - fuel mixture explodes. This downward motion then
Pit Board	(1) A signboard on the end of a long pole that the pit crew uses as a flag to their driver, so that the driver can find the proper pit, and to indicate, when executing a pit stop, exactly where the driver should stop. (2) Back in the bad old days before d
Pit Box	A rectangle painted on the pit lane that shows exactly the area where servicing is permitted for each team.
Pit Road/Pit Row/Pits	An area adjacent to the track surface (generally in the infield) where cars are serviced. The name comes from early days of racing in which the pits actually had holes or pits dug in the ground so the crew could work on the underside of the car.
Pit Stall	A rectangle painted on the pit lane that shows exactly the area where servicing is permitted for each team.
Planetary Transmission	A transmission in which the various gears revolve around one another. Consists of a sun gear, carrier with planet gears, and ring gears. Also known as overdrive or underdrive.
Plate	(1) A Restrictor Plate: A device used to control power at tracks where the cars would otherwise be too fast for safety or insurance reasons. The plate is a machined slab of aluminum, about 1/20" thick, with four holes of a specific size. The plate goes in
Plate Engine	An engine designed to run with a restrictor plate.
Plowing	When the car is pushing up the track in the turns.
Plug Check	During a practice or a qualifying session, if a driver shuts off the engine while at full power and then coasts into the pits, it is generally so that the crew can perform a plug check. The spark plugs are removed and the electrodes and insulator examined
Plus-Sizing	An option allowing drivers to customize their vehicle by mounting low-profile tires on wider rims of one or two inches greater diameter, usually enhancing vehicle appearance, handling and performance.
Ply	A rubber-coated layer of fabric containing cords that run parallel to each other; extends from bead to bead.
P-Metric	Designation of tires built to DOT regulations. "P" indicates Passenger vehicle. Metric refers to the nomenclature and labeling requirements. Uniform designation of tire sizes, in metric measurements originally introduced by American tire manufacturers in
Pneumatic	Refers to a device or tool that uses air for support or power.
Pneumatic Tire	A tire designed to use air for it support.
Points	A points system rewards drivers with points based on where they finish in a race, and may contain opportunities for earning bonus points by doing things like winning the pole position or leading a lap. At the end of the season, there is often a large cash
Pole	The first starting position in a race; the inside of the front row.
Pole Sitter	The car occupying the first position in a race or the fastest qualifier for a race. Note that, due to qualifying procedures, the pole sitter may not always start from the first position due to inversion. In many racing series, the pole sitter has the opti
Polish Victory Lap	An extra lap, run by the winner of a race, around the track in the reverse direction, and usually completed with a 180-degree spin at the start-finish line. The Polish victory lap was a creation of the late Winston Cup champion Alan Kulwicki, and several
Polymer	A long-chained molecule such as rubber. On a molecular level appearing like a bunch of interlocking spaghetti.
Pop-Off Valve	A mechanism used by CART to limit engine power in its turbocharged Indy cars. It is a valve that limits the pressure boost that the turbocharger can produce. If the boost pressure exceeds the pop-off valve's setting, the valve opens and vents the pressure
Porpoising	An undesirable condition in which the racecar is bouncing up and down due to improper setup.
Port	The opening in an engine where the valve operates and through which the air-fuel mixture or exhaust passes.
Post Entry	A race team that enters a race after the race's official entry deadline has passed. Most sanctioning bodies will allow post entries to participate in a race, but will penalize it for the late entry monetarily or by not awarding it championship points for
Powder Puff	A name used, back in the chauvinistic '60s, for a race or racing division where all the competitors were women. At many tracks, powder-puff races often consisted of wives of drivers or car owners in a very short race, using their husbands' cars.
POWER	Prototype Open Wheel Economy Racing Series.
Power Plant	Commonly used term for engines.
PPI	Pounds per inch. A rating used in suspension parts such as shocks and springs. Used to measure the amount of weight that needs to be applied to attain 1 inch of travel.
Pre-Staged Light Beam	Light beam used to warn drivers they are inches away from starting line. This beam when broken by front wheels sets off pre-staged bulb on top of the Christmas tree.
Primary Sponsor	The sponsor that puts up the bulk of the sponsorship money for a race team, and consequently gets the most exposure on the car.
PRL	Provincial Racing League:
Professional	A participant who makes his or her living off of racing. Unlike some sports, in auto racing there is no controlling body determining who is entitled to amateur or pro status, although some sanctioning bodies do require drivers to meet qualifications befor
Profile	Used to describe the shape of a tire.
Progressive Spring	A spring that needs an increasing amount of force to increase deflection. For example, 1-inch of deflection for the first 200 pounds but the 2nd inch of deflection needs 500 pounds instead of 400. See Linear spring.
Promoter	Someone who organizes a race, puts up the purse, gets race sponsors, handles advertising and ticket sales, and assumes the financial risk of putting on the race. The promoter might be a track owner, the owner of rights to a series, or an independent.
Promoter's Option	The traditional prerogative of the promoter, as the person who organizes a race, of designating one or more cars to start a race even though they failed to qualify. Promoters often reserved an option for themselves, so that they could be guaranteed that a
Pro-Street	A highly modified streetcar. Pro-street cars generally feature large engines, blowers, narrow rear ends, and tubbed fenders. Older muscle cars like the Camaro and Chevelle are popular.
Protest	A complaint filed with officials, generally used to check for illegal components, scoring errors, or inappropriate driving techniques. Often, a fee is charged to file a protest, with the money returned if the competitor is found in violation.
Pro-Tree	The method of starting cars from starting line, using the Christmas tree. Method used is all three yellow bulbs light then green as opposed to one yellow light at a time then green (full tree). Also uses a reaction time of .400.
Provisional Start	A system used by many touring series that provides extra starting spots in the main event for teams that participate in a series on a regular basis. Provisionals are generally based on point standings, earnings, or past championship victories.
PSI	Pounds per Square Inch, a measurement of air pressure.
Pucker Factor	A high level of fear over an incident or difficult racing situation.
Pump Gas	Street-legal gasoline that can be purchased by the public. Used to distinguish from racing gasoline at many weekly racing tracks, the lower divisions are required to use pump gas (which has a relatively low octane rating compared to racing gas) as a way o
Punt	To bump someone from behind, usually causing a spin.
Purging	Process of removing air from a tire and replacing it with drier air, nitrogen, or another gas in order to lower humidity in a tire. This may be repeated several times in order to achieve even lower humidity.
Purse	The total prize money to be awarded to the race participants by the promoter. See also contingency awards.
Push	1) A handling condition where the front wheels tend to slide when turning into a corner, which makes the car want to keep going straight. "Pushing like a dump truck" Push is the opposite of loose. Sometimes referred to as understeer. 2) Push starting a ve
Pushrod	1) Engine: A rod that carries force from the camshaft of a pushrod engine, to a rocker arm (which transmits the force to the valve). The term also refers to engine designs that use pushrods. Such engines generally have a single cam, which on a V-shape eng
Pyrometer	In general, a heat-measuring device. The most common racing use is the tire pyrometer, which is used to measure surface temperatures of different areas on a tire and assist in chassis setup. Other common pyrometers include those designed to measure the te
QMA	Quarter Midgets of America.
Quad	Refers to a four-wheel all terrain vehicles.
Quad Oval	A tri-oval variant, which has two doglegs in the front straight instead of one, which increases the number of seats, which are directly in line with some part of the front straight. Charlotte and Texas are examples. (Atlanta, originally a conventional ova
Qualifying	The act of running a timed lap to earn a starting position in a race. In nearly all forms of oval track racing, qualifying consists of one car at a time running one or more laps to try to record the fastest time, for the best starting position. In road ra
Qualifying Trim	Special setup used during qualifying whose purpose is to make the car go as absolutely fast as possible for only one or two laps.
Quarter Midget	A miniature version of a Midget. Quarter midgets are very small single-seaters, similar in proportions to a kart, but with full bodywork and a sprung suspension. Most also have some type of roll cage.
Quarter Panel	The sheet metal on both sides of the car from the C-post to the rear bumper below the deck lid and above the wheel well.
Quick-Change	A type of rear end gear, which is designed so that the final drive ratio can quickly be changed without removing the rear end from the car.
Race Rubber	Tires used just for the race as opposed to qualifying.
Race Safe System	A warning system that alerts a driver of a caution. Usually by an in car indicator light activated by a Race Official.
Racing Back to the Flag	When a caution or Yellow flag condition occurs and cars race to cross the finish line in order to better their restart position.
Racing Gasoline	Gasoline designed specifically for racing engines. Racing gas usually has very high octane.
Radial Ply Tire	A type of tire that's constructed with the reinforcing belts sideways (bead to bead) under the tread rather than lengthwise. The cords in the body of a radial tire run at or near 90-degree angles to the centerline of the tread. The combination of stabiliz
Radius	1/2 the diameter of a round object. The measurement from the center of an object extending to the outer surface.
Rain Tires/Rains	Tires used during wet conditions. Usually grooved to channel water away from the center of the tire in order to have a good contact patch. Also referred to as wets.
Rake	Term used to describe the angle of the chassis compared to the ground.
Ratchet Rear End	A rear end gear that locks under acceleration, and unlocks when the driver lets off the throttle. Commonly used in oval-track racing, where it provides the straight-line acceleration of a locked rear end, without the cornering difficulties.
RCCA	Race Car Club of America. Sanctions Formula racing events in the United States.
Reaction Time	In drag racing, this is the time elapsed before your front tires leave the staging beams after the green light is illuminated. Generally computed in thousandths of a second. .400 (pro-tree) and .500 (full tree) are perfect reaction times.
Rear Clip	The section of a race car that begins at the base of the rear windshield and extends to the rear bumper. Contains the car's fuel cell and rear-suspension components.
Rear End	Racer's term for the differential, the set of gears that transfers power from the driveshaft to the rear wheels. Racing rear ends may be locked. Stock cars usually require cooling fans or radiators to dissipate the heat that builds up due to losses that a
Rectangular Track	A variant of an oval track that has the two numbered turns at each end of the track (which, in a normal oval, are combined into 180-degree corners) separated by "chutes", short lengths of straightaway. From the air, the track has the appearance of a recta
Red Flag	Race halted; all cars must drive slowly around to the start-finish line (or some other point designated by the officials) and then stop. Used when the track is blocked, or needs repair, or when weather conditions make it unsafe to continue even at caution
Red with Yellow "X" Flag	Indicates that the pits are closed. When a caution occurs, the pits are closed until the pace car has entered the track and the field is formed up behind it). An official positioned at the pit entrance holds this flag. Any car that passes this flag and en
Redline	Usually, the maximum RPM that an engine can be safely operated at; indicated by a red pointer or painted line on the tachometer. Many modern racing engines have a rev limiter that will momentarily cut off the ignition to prevent the redline from being exc
Relief Driver	A driver who, during a race, takes over a car for another driver who is physically unable to continue (due to factors such as illness, dehydration, or previous injury).
Rental Ride	When a team or driver pays a car owner for use of a team and/or car for an event.
Repeatability	A tires ability to be used many times.
Reset Fuel	Indy cars do not have fuel quantity gauges. Since Indy cars are equipped with engine computers, they have devised a method for estimating the amount of fuel remaining: by placing a flow meter in the fuel line, and having the computer integrate the flow ov
Restart	The term for the resumption of a race after a caution period.
Restrictor Plate	A device used to control power at tracks where the cars would otherwise be too fast for safety or insurance reasons. The plate is a machined slab of aluminum, about 1/20" thick, with four holes of a specific size. The plate goes in between the carburetor
Retaining Walls	Barriers lining the inside and outside of a racing surface used to contain cars and debris from the spectators.
Retire	As used in racing, to drop out of a race due to mechanical difficulties or irreparable damage. Also used, however, in the conventional sense, as in to retire from the sport.
Return Road	In drag racing, a road which leads from shutdown area back to the pits or staging lanes. Often, return roads are placed between the drag strip and the grandstands, allowing spectators to view the cars better and to reward great runs with rounds of applaus
Rev Limiter	A device that limits the maximum RPM that an engine can reach, usually by momentarily cutting out the ignition when the set limit is reached. The rev limiter (often a standard feature of modern racing electronic-ignition units) can be set to prevent the e
Reverse Cooling	A method of routing engine coolant to reduce differences in temperature between different parts of the head in block. A conventional cooling system has coolant from the radiator flowing into the block's water jacket, where it flows upwards towards the top
Rib Tire	A tire produced from the factory with only the circumferential grooves molded into the tread. Generally, rib tires are grooved by hand to match the track conditions.
Ride Height	The distance between the car's frame rails and the ground.
Riding the Rails	Used to describe a car or driver that is driving in the outer most portion of the track.
Rim	A wheel, technically, a metal support for a tubeless tire or a tire and tube assembly upon which the tire beads are seated.
Rim Protector	Portion or extension of the sidewall of the tire that prevent rim damage during contact.
Rim Width	Distance between the two opposite inside edges of the rim flanges.
Road Course	A closed-circuit racecourse containing both left- and right-hand turns, and designed to approximate the experience of driving on open roads. Road courses may be built to run either clockwise or counterclockwise; they often contain changes in elevation or
Roadster	(1) A general name for a single-seat or two-seat sports car. (2) In drag racing, a general description of a drag racing vehicle featuring an open cockpit, tubular frame, offset driving position, and cut down body from a passenger vehicle. Unlike an "alter
Rollback	A flatbed truck equipped with a winch, used to retrieve cars that have been so badly wrecked that they can't be towed.
Roll Bar/Roll Cage	The steel tubing inside the racecar's interior. A U- or V-shaped bar that protrudes from the top deck of an open-cockpit car, higher than the driver's head, such that if the car rolls, the car's weight will land on the bar instead of the driver's neck.
Roll Center	The theoretical point where suspension components intersect. This defines the point of rotation for the "lean' or "roll' when cornering. In practice, this point changes as the suspension moves up and down. For racecar design it is used in connection with
Roll Couple	Refers to the percentage of how much resistance to body roll is distributed between the front and the rear suspension systems.
Rolling Resistance	The measured drag create by a driving surface, the tire, drive train parts, or a combination of all. The lower the rolling resistance, the less energy needed to keep a vehicle moving.
Rollout	The circumference of an inflated tire. The measured distance a tire will cover in one revolution.
Roof	Panel over the top of the driver's compartment.
Roof Flaps	A set of trap doors in the roof of a stock car. The roofs of these cars, since they are usually shaped somewhat in profile like an airplane wing, tend to generate lift when the car gets sideways, and on a superspeedway, this lift can be strong enough to a
Roof Net	webbing, similar to a window net that covers the opening in the top of the roll cage. Its function is to keep the driver's arms in the car in case the roof sheet metal gets torn off the car in a roll or flip. Invented by Robert Yates and Davey Allison.
Roof Strips	Strips of metal that run lengthwise on the roof of a stock car. These are designed to disrupt the airflow over the car if it becomes sideways. This kills the lift created and keeps the car from becoming airborne.
Rookie	In general, a driver who is inexperienced in the type of cars he/she is currently running. In most series a rookie is required to put a yellow stripe on the back of their car to notify other drivers.
Roller	A complete racecar minus an engine.
Rotating Mass	Somewhat misleading term for the combined angular momentum/inertia of all of a car's rotating propulsion parts such as the crankshaft, flywheel, and drive shaft. Engine and car designers have recently come to understand that high angular inertia has an ef
Rotation	The changing of tires from front to rear or from side-to-side on a vehicle according to a set pattern; provides even tread wear.
Rotor	The disc portion of the brakes.
Round	When all cars in a bracket or class have made a run, usually, an elimination run.
Rounds	The number of revolutions a wrench, nut, or bolt is turned. One and a half rounds are one and half revolutions.
Rounds of Wedge	Adjusting the handling by changing the pressure of the rear springs. A wrench is inserted in a jack bolt attached to the springs, then turned
Roundy Round	Phrase used to describe a circular or oval track.
Roval	Slang term that combines the two words Road (course) and Oval. Describes an oval track such as Daytona or Homestead that has a road course in the infield. Events such as the Daytona 24 hour race use the road course as well as a large portion of the oval t
RPM	Revolutions Per Minute.
Rub	Light contact between two cars or two parts.
Rubber	1) The blend of rubber and other chemical and natural components that form the surface of a tire. Race tire rubber is not purely natural rubber, but a blend of natural and synthetic rubbers with chemicals and oils. 2) A semicircular wedge of rubber that i
Rubbing	Minor contact between cars.
Run Under	In Drag racing, when your elapsed time is quicker than your dial-in, this causes you to be disqualified.
Running at Finish	A statistical classification; the opposite of DNF. A car is classified as having been running at the finish of a race if it crosses under the checkered flag. Note that this does not represent how many laps the car may have lost during the race.
Running Light	A car that is low of fuel.
Running the Double	Recent term for competing in the Indianapolis 500, and the Coca-Cola World 600 at Charlotte, in the same day.
SAE	Society of Automotive Engineers. The professional association of transportation industry engineers that set standards for testing, measuring, and designing automobiles and its components.
Safety Bead	A hump that is present on the mounting flange of a wheel. This prevents the tire from unseating when air pressure is lost.
Safety Lap	An extra lap or laps run at racing speed after taking the checkered flag.
Safety Liner/Shield	Same as an inner liner. A safety device for racing tires. An inner liner is a sort of tire-within-a-tire; it has its own air containment and its own valve stem separate from the main carcass of the tire. The inner liner is inflated to a pressure higher (u
Saloon Cars	A British term for Stock cars or sedans.
Sanctioning Body	An organization that sets and enforces the rules for a race or racing class or series.
Sandbagging	Deliberately running slower than the car is capable of, particularly in practice or the early stages of a race in order to surprise the competition in the race.
SARA	Southern Auto Racing Association.
SAS	Southern All Star Racing Series or Sprint Asphalt Series.
SATCAR	Sports And Touring Car Racing.
Sawing On The Wheel	Expression describing when a driver turns the steering wheel back and forth in a rapid manner.
SBRA	Southern Bracket Racing Association.
SCCA	Sports Car Club of America, a body that sanctions a variety of road racing activities. The SCCA focuses mainly on sports car racing, and most of the SCCA's series and divisions are amateur or semi-pro, but its Trans Am series is a highly regarded pro seri
SCCS	Stock Car Championship Series.
SCDCA	Southern California Dwarf Car Association.
SCOA	Sprint Car Owners of Arizona.
Scoring Line	A line on the track, where a car's scorer registers the car as having completed a lap when the car crosses that line. At larger tracks, the scoring line (or lines) is often not the start-finish line and vice versa.
Scotch	Refers to good side bite or tire grip in the middle of a turn.
SCRA	Sprint Car Racing Association. Sanctions non-winged Sprint car racing events in the United States.
Scrub	When a tire does not rotate in the same direction or with the same speed as the car moves, it scrubs over the surface. This is sometimes done intentionally to heat, clean, and/or harden tires.
Scuffs	In general, any tire that has been used, but usually refers specifically to tires that have been run for a few laps, removed from the car, allowed to cool, and then put aside for later use. Scuffing changes the physical characteristics of the rubber, gene
Seat Time	Used to describe time spent in a racecar.
Section Height	The distance between to bead diameter and the outer diameter of the tire. This dimension is usually represented as a percentage of the tread width.
Section Width	The width of the tire at the widest point when mounted on the correct rim. This is typically located somewhere about the midpoint of the sidewall.
Seize	When an engine locks up due to mechanical failure. This may result from overheating or a part breaking.
Self-Cleaning	Said of high-banked tracks, where wrecked cars and debris tend to slide off of the corners into the infield. Drivers at such a track have to be careful when approaching a spin or wreck in progress, since the out-of-control car will eventually slide off th
Self-Starting	An engine equipped with an onboard starter, as opposed to using an external starter, which is attached to the engine to start it, and then removed (or simply pushing the car to start it). Most forms of Stock car racing require self-starters while Indy car
SEML	Small Engine Motorsports League.
Sequential Shift	A type of semi-automatic transmission where the driver can select the next highest or lowest gear by just moving a lever or pressing a button. Some sequential-shift gearboxes are purely mechanical, but in others actual movement of the gears, as well as op
Series	(1) Tires with the same aspect ratio, or relationship of height to width inside the tire. (2) Common description used for the races sanctioned by a specific organization (touring series).
Setup (chassis)	The configuration of the chassis in order to achieve the desired handling. Generally this consists of a selection of springs, shocks, and other suspension components with the needed force and damping characteristics, plus adjustments like camber, caster,
Shake Down	Testing a brand-new car or engine.
Shaving	A process of removing tread. It has been shown that a tire with a thinner slick tire performs better than a thicker treaded tire.
Sheet Time	Time spent in a hospital, or otherwise rehabilitating from an injury.
Shift Points	The best engine r.p.m. at which to shift gears. Some production and racecars have lights to indicate when a driver should shift gears.
Shimmy	Wobbling of wheels from side-to-side on a vehicle. Shimmying can be caused by a variety of factors, including improperly balanced tires, poor alignment and bent wheels.
Shock	Component designed to control the up and down movement of the suspension caused by weight transfer as well as changes in the road or track surface. A shock controls the speed at which the spring moves. Shocks are rated in pounds per inch (ppi) or how many
Shoe	Term used to refer to a racecar driver.
Shoes	Slang term for tires.
Shoe Up/Change the Shoes	Slang term for changing the tires.
Shoot Out	Two or more driver's that are racing for the victory.
Short Block	Refers to a stage of assembly of an engine (and the state of assembly that engines might be sold in). Engine assembly ranges from "bare block", which is just an engine block with no moving parts, to "short block", which is a block with crankshaft, rods, a
Short Track	An oval track usually less than 1 mile in length. It is characterized by close, physically challenging competition, frequent contact between cars, and usually short races. The short straights and relatively slow lap speeds make handling and driver ability
Shoulder	The area of a tire where the tread and sidewall meet.
Showroom Stock	A racing series where new production cars are raced with very few or no modifications. Currently, this classification is limited mostly to road racing and Solo II events.
Shunt	British term for a collision.
Shutdown Area	In drag racing, the area located after finish line for racing cars to slowdown.
Shut the Gate	Slang term for blocking another car from passing.
Side Bite	A general term used to describe the amount of force available to hold the car in the apex of a corner. In car setup, putting more side bite in usually refers to reducing the sliding motion of a car in the corner.
Side Pod	The part of the body of an Indy car that extends into the space between the front and rear wheels. In a modern Indy car (since about 1972) design, the sidepods contain the engine's radiator and oil cooler; the sidepods contain tunnels that control the air
Sidewall	That portion of a tire between the tread and the bead.
Silly Season	Slang for the period during the latter part of the current season, wherein some teams announce driver, crew, and/or sponsor changes for the following year.
Silver Crown	A type of car defined by USAC, and the USAC series that runs these cars. Silver Crown cars follow basic Sprint car design except they're longer, heavier, and slower. Silver Crown is sort of the successor to the old front-engine Championship roadster cars
SIMS	Southern Independent Modified Series.
Sipes	Special slits within a tread that can increase traction. Most often used in dirt track applications.
Sipping	A term used when a tool with a very narrow blade is used to alter the tread pattern of a tire. When using this tool it will create a slice in the tread surface. This process is used to help a tire take off better on starts and to also help with heat dispe
Size	The combination of tire width, construction type, aspect ratio and rim size used in differentiating tires. May also refer to the circumference of a tire when inflated to race pressure.
Skid	To slip or slide on the road when tires lose their grip.
Slicks	Racing tires having no tread design, in order to get the maximum amount of rubber in contact with the pavement.
Slick Track	A track that has become slippery due to weather or a liquid spill.
Slide Job	A passing technique seen at dirt tracks. It involves diving into the bottom of a corner, under the car to be passed, at a speed far too high to maintain that line. As soon as the passer is clear of the car being passed, he allows the car to drift up the t
Slideways	Slang term that combines the words sliding and sideways. Means doing a combination of both.
Slingshot	When a trailing car is able to draft and attain a higher speed, allowing it to run up on the leading car and pass.
Slip	Elastic deformations of a tire during acceleration and cornering. These deformations affect the contact patch and ultimately the amount of grip.
Slip Angle	The angle between the direction the tires centerline are pointed and the direction the tires are actually going.
Slipstream	The cavity of low-pressure area created by a moving object. In racing, drivers use this slipstream to draft another vehicle.
Small Block	Usually refers to a small-block Chevy engine. This is by far the most commonly used engine in all forms of Stock car racing. Introduced in 1955, this engine design is probably the longest-lived internal-combustion engine design ever. A small-block Chevy i
SMART	Southern Modified Auto Racing Teams.
SMRA	Southern Midget Racing Association.
Snaking	On a superspeedway, driving a meandering path down a straight, in an attempt to cause following cars to get out of line and lose the draft.
Snow Tire	Sometimes called winter tire; a special type of tire with a tread and compound that gives better traction in snow; identified by the M+S, M&S, or M/S on the sidewalls. All-season tires must also include these designations on the sidewall.
SOD	Sprints On Dirt.
Soft Walls	A type of racetrack wall construction that uses softer materials and spacer designs to absorb impact energy.
SOHC	Single overhead cam.
SORA	Sprint 100's Racing Association.
SOS	Southern Ontario Sprints
SOSS	Southern Outlaw Super Series.
Spec	A type of rule that specifies a legal and required part by brand name or model, as opposed to a technical outline that leaves the choice of parts and brands up to the individual teams. Spec rules (tires are a common example) are often used by tracks to co
Speed Rating	An alphabetical code (A-Z) assigned to a tire indicating the range of speeds at which the tire can carry a load under specified service conditions.
Speed Trap	On a drag strip, the final 66 feet to the finish line, known as the speed trap, where speed is recorded.
Speedway	A racetrack.
Speedy-Dry	A trade name for a granular mix of sand, cement, and resin used to soak up spilled oil, water, etc., from a racetrack. Has become the generic name in racing circles for any material used to soak up a spill.
Spin and Win	A race in which a car spins during the race but then ends up winning.
Splash-and-Go	A very short pit stop in which a small amount of fuel is added to the car and no tires are changed. Often seen near the end of a race, when a team calculates that they will be just short of having enough fuel to finish the race.
Splice	The point at which a one-piece tread or other tire components come together.
Split	1) A measurement of time over a fixed distance, usually less than an entire lap. Seen mostly in road race and drag race timing. For example, the time it takes a car to go from turn 2 to turn 6 on a 13-turn road course. Can pinpoint places for improvement
Split Valve Shock	A shock with a different rated ppi for compression and rebound.
Spoiler	An aerodynamic device used to increase downforce. On a Stock car, there typically is a spoiler on the rear edge of the deck lid, which produces downforce on the rear by causing air to "pile up" against the deck lid. Front spoilers were once similar, but n
Sponsor	A person or company who gives support money and/or products to a series, driver and/or team in exchange for advertising or some other benefit.
Spotter	Found in series where drivers are permitted to use radios. A spotter is someone who sits in a high place (typically on top of a grandstand roof) and watches their car, and the track ahead of their car. The spotter advises the driver when there is a car to
Spring	Coil springs are located at each corner of the chassis. The springs determine how much weight is transferred to each corner of the car. The springs are mounted in such a way that they can be adjusted up or down to change ride heights. Springs are rated by
Spring Rate	Amount of force measured in pounds needed to achieve a certain amount of deflection. Used in rating springs and tires.
Spring Rubber	A semicircular wedge of rubber that is inserted between the turns of a coil spring to increase the spring's rate. Spring rubbers are often inserted into a spring prior to a race, when the team suspects that they will have to make a large handling adjustme
Sprint	An open wheel style of cars similar to, but somewhat larger than, Midgets. Engines are generally V-8, normally aspirated, and injected. Sprints are run on both dirt and paved ovals. Sprint cars are divided into two broad categories: winged and non-winged.
Spun Bearing	A type of engine failure. The main bearings (that hold the crankshaft in place in the block), and the rod bearings (that connect the rod to the crankshaft) consist of thin semi-circular pieces of special metal alloys that contain the rotating parts, and t
Squat	The action and ability of a racecars rear end to stay down in order to get good contact and grip.
Squirrelly	Used to describe an ill handling car, usually loose.
SRL	(1) Scale Racing League sanctions Mini cup, mini truck, and slingshot racing. (2) Super Modified Racing League. Sanctions Super Modified racing.
SSMA	Sourthern States Midget Association.
Staged Light Beam	Light beam used to warn drivers they are on the starting line ready to race. This beam when broken sets off staged bulb on top of the Christmas tree. This beam also determines reaction time.
Stagger	A difference in circumference between the left-side and right side tires on a car. In a car with a locked rear end, rear-tire stagger will make the car want to continuously turn in the direction of the side with the smaller circumference tire.
Staging Director	A person who directs the flow of traffic from the staging lanes to the race lanes.
Staging Lanes	In drag racing, lanes located behind the starting line area where drivers line up and wait to make a run down the track. Usually, each class is called to the track by their particular staging lane.
Standing Start	A type of race starting setup in which the cars are lined up and started from a standstill instead of a rolling start.
STAR	Senior Tour Auto Racers.
STARS	Battle of the Bluegrass Tour.
Start and Park	Term to describe a car that starts the race then pulls into the garage after only one or a few green flag laps. This is usually done for several reasons: to fill out the field to meet the advertised car count, pick up prize money for a finish without spen
Starter	(1) A device used to start an engine; a self-starter or an external starter. (2) A truck used mainly to push-start race cars commonly seen at Sprint and Midget races where the cars lack any other starting mechanism. (3) A flagman.
Start-Finish Line	A line on the track where the race officially begins and ends. The flagman's stand is usually at the start-finish line.
Static	Dimensions or descriptions that apply to an object that is not in use or in motion.
Steering	Changing the direction of a vehicle or the components used to do so.
Stick	The amount of tire grip present.
Stick-and-Ball	Race fans' derisive term for almost any sport other than auto racing, but particularly the American "big three" of baseball, football, and basketball. Hemingway once said: There are only three true sports mountain climbing, bullfighting, and auto racing.
Sticker Tires	Tires that have never been run on a car, and still have the manufacturer's sticker on them. The stickers can easily be seen on the tires when a car equipped with sticker tires leaves the pits. See also scuffs.
Stiction	Slang term for tire grip. Combination of the words
Stock Cars	Cars based on the body and (sometimes) chassis of mass-produced streetcars. Stock cars can range from no-modifications-allowed Showroom Stock and Hobby/Bomber classes, to the Winston Cup cars which run with stock body shapes and stock-block engines, but a
Stock-Block Engine	The definition of this term is rather vague. In most usage's, it generally refers to an engine that is based on a production engine block design (specifically, that certain essential measurements of the block such as the cylinder-to-cylinder spacing or de
Stop-and-Go	A type of penalty, which calls for the driver to drive the car to the pits, stops, and then immediately leaves again. This penalty is usually imposed for moderate infractions, such as going too fast in the pits, or passing improperly during a restart.
Stopping Short	A type of pit strategy which involves making a pit stop prior to the time where tire wear or fuel depletion would make it necessary. This strategy is often employed at tracks where the average lap time is greater than the time required to make a pit stop.
Street Circuit/Course	A road course made up partly or wholly of partitioned-off city streets. CART and many open-wheel formula road-racing series run on street circuits. There is considerable debate about the quality of racing that ensues; often the streets are too rough for h
Stressed Member	Term used for a method of construction, seen mainly in open wheel cars, where the engine, rather than being supported by the chassis, is part of the chassis. On an IRL car, for example, the tub ends behind the cockpit, and the engine bolts on to a bulkhea
Stringing	A procedure for checking the toe of the front wheels. Basically, it consists of running a string down the side of the car; with the steering wheel pointed straight ahead, the distance between the front edge of the wheel and the string, and the rear edge o
Stroking	(1) Driving conservatively so as to preserve the equipment and stay out of accidents. Drivers who do this consistently are known as "strokers" and the term carries some scorn, but sometimes stroking is necessary when a car is known to have a problem that
Submarining	A term for when the driver slides out from under the lap belt in a high-speed frontal impact.
SUMA	Southern United Modified Association.
Supercharger	An air compressor, powered by the engine (via a drive belt, gear, or shaft), which forces more air into the engine. On most internal-combustion engines, the upper limit on power output at a given compression ratio is determined by the amount of air that c
Super Modifieds	An extreme form of Modifieds, rapidly distinguished from them by the fact that Super Modifieds are open-cockpit. Super-Modifieds use an offset big block engine that produces 900 horsepower for an 1800-lb car.
Superspeedway	An oval track that is usually greater than 1.5 miles in length. Note that the IRL uses a different classification. In IRL usage, a 1-mile track is a short track (the IRL doesn't race on tracks shorter than one mile), and anything longer than 1 mile is con
SUPR	Southern United Professional Racing.
Surface Plate	A large flat metal surface used as a dimensionally stable and level platform for the construction or alignment of a chassis.
SVRA	Sports car Vintage Racing Association.
Sway Bar	See anti-roll bar. Bar used to resist or counteract the rolling force of the car body through the turns.
Sweeper	A large sweeping corner on a road or street course.
Switchback	An "S" like track configuration generally designed on a fast portion of a track to slow cars.
Switching Ignition	Changing from a primary to a backup ignition unit. The driver can change from one unit to the other, in a manner of a few seconds.
Tachometer	Also referred to as a Tach. A gauge that measures revolutions per minute.
Tacky	A track condition where the racing surface is slightly wet and sticky.
Taking Rubber	A dirt track term describing when a racetrack loses its moisture and rubber from the tires begins to stick to the dirt surface, creating an asphalt-like condition. Tires wear much quicker in these situations and races are generally less interesting as onl
Taking the Air	When two cars are close together and the lead car has less air being applied to its rear spoiler. This causes the car to have less rear downforce, which causes it to be loose in the turns.
Talent	Used to describe a driver
Tank Slapper	A violent oscillation in the front end of a motorcycle. So violent that the rider ends up repeatedly hitting or slapping the gas tank with his/her legs or another body part. Can also be used in auto racing to describe an accident in which a cars back end
TBARA	Tampa Bay Area Racing Association.
T-Bone	An accident where one car runs into another hitting it at a 90-degree angle directly in the side.
T-Car	In Indy car racing refers to a backup car. Traditionally, in Indy car racing each car that a team brings to a race has to have its own entry filed (as opposed to the practice in NASCAR where one entry covers a team's primary and backup car). So that each
TDCA	Texas Dwarf Car Association.
Tear-Off	(1) A layer of clear plastic that covers the visor on a full-face helmet. The tear-off is attached with a weak adhesive, and has a tab so that the driver can rip it off and remove it when it becomes dirty. Some tear-offs have several layers, each with its
Tech	Short for Technical Inspection, an area and/or process in which Officials inspect vehicles for rule and regulation compliance.
Telemetry	A radio system that gathers data about the car's performance from sensors, and passes that data directly to the pits via radio, without any effort on the part of the driver.
Template	A metal, wood, or plastic cutout used to check the body dimensions of a car. Often used for Stock cars, which usually must conform to rules requiring them to maintain at least a semblance of the body shape of a production car model. NASCAR introduced temp
Ten-Tenths	Slang term for running at the maximum.
Tenths	1/10th of a second. Used in timing lap times. The first digit to the right of the decimal point. Sometimes even broken down to a half a tenth, which is equal to 5/100ths (five one hundredths) of a second.
Tethers	steel cables which are attached to the car's wheel hubs and assembly, as well as the hood and various pieces of sheet metal, to prevent these parts from flying off the car during a high speed crash.
Thousandths	1/1000th of a second. Used in timing lap times. The third digit to the right of the decimal point. Threshold Braking: Braking hard, but below the point where the tires lock up and begin to skid.
Throttle	The plate(s) used to control the air/fuel delivery system that controls the output of the engine. Also refers to the gas pedal and all components that control acceleration.
Tight	A handling condition where the front wheels tend to slide when turning into a corner, which makes the car want to keep going straight. Also called push or understeer. Tight is the opposite of loose and oversteer.
Time Runs/Time Trials	Also referred to as
TIN	Tire Identification Number. An alphanumeric code mark located usually on the sidewall of a tire to identify a manufacturing batch or date.
Tire	An assembly of rubber, chemicals, fabric and possibly metal, designed to provide traction, cushion road shock and carry a load under varying conditions.
Tire Designation	An alphanumeric code molded into the sidewall of the tire that describes the tire's size, including width, aspect ratio, rim diameter, load index and speed rating. Most designations use the P-Metric system, although racing tires often use non-DOT nomencla
Tire Placard	A metal or paper tag permanently affixed to a highway vehicle, which indicates the appropriate tire size and inflation pressures for the vehicle.
Tire Rub	When a tire is coming in contact with part of the car.
Tire Run	The amount of laps or time run during the useful life of a set of tires.
Tire Rule	When a racing series mandates that competitors can run only one "spec" or specified brand of tires. See "Spec.":
Tire Shake	A drag racing phenomenon when a loss of traction and/or tire distortion causes the tires to shake violently. Normally, the car becomes out of control and the driver's vision is blurred from the movement. See also back-pedaling.
Tire Softener	A solvent, which is applied to the surface of tires, changes the chemical characteristics of the tread rubber. Sanctioning bodies and most weekly tracks have banned the use of tire softeners because they are based on aromatic hydrocarbons (such as benzene
Tire Stint	The amount of laps or time run during the useful life of a set of tires.
Tire Wear	The loss of rubber from tire treads due to use.
Toe	(1) This is the area of the bead that describes the point of termination of the bead. (2) One of the three major suspension geometry adjustments. The angle of the wheels, relative to the car's forward motion. With the steering wheel in the straight-ahead
Toe Steer	Changes in the direction of a wheel or wheels due to deflection of suspension parts. Usually during cornering or driving on an uneven surface.
Top End	(1) The parts of the engine above the cylinders, including the cylinder heads and valves. Compare with bottom end. (2) The part of an engine's RPM range near the redline.
Top End Power	The amount a car accelerates at high speeds or in its highest gear.
Top Wing	An airfoil, used to generate down force to improve handling characteristics and improve traction. It's size is normally around 5' x 5'. This wing is generally mounted directly above the roll cage.
TORA	Topless Outlaw Racing Association.
Torque Steer	The tendency of a car to steer a certain direction when power is applied.
Torsion Bar	A rod in the suspension system that, when twisted from a grip at one end, functions like a spring.
TQ	Abbreviation for "three-quarter" midget, a sort of downsized Midget. TQ's are run at some tracks as a support division to train drivers for Midgets and Sprint cars.
Track	A racing surface. Racetrack or racing facility.
Track Bar	In a Stock car rear suspension, a lateral bar that prevents the axle from moving left or right. It is generally attached to the end of the axle housing on the left, and to a frame bracket on the right. Also called a Panhard bar.
Tracking	The direction an object is moving. May be different than the direction the object is pointing.
Track Out	The point on the track exiting a turn where the car comes closest to the wall.
Track Temperature	The temperature of the surface of the racetrack.
Track Width	Refers to the overall width of the axles, from their widest points. Usually, track width is measured from the centerline of one tire to the centerline of the other.
Traction	The friction between the tires and the road surface; the amount of grip provided.
Traction Control	Devices used to limit acceleration to only the amount beneficial for traction.
Trading Paint	Slang term used to describe aggressive driving involving a lot of bumping and rubbing.
Trail Braking	When the brake is applied after steering into a curve. Traditionally in racing, brakes are applied while the front wheels are still steering straight. Trail braking may allow deeper braking into a corner, but if not done properly can very quickly result i
Trailing Arm	A rear suspension piece holding the rear axle firmly fore and aft yet allowing it to travel up and down.
Tramping	A state in which a vehicle bounces up and down abnormally. If the bouncing is localized to the rear tires while under power, the car is said to be experiencing "wheel hop".
Trans Am	A road-racing series for sedans, sanctioned by the SCCA. Trans Am cars are based around American-made sports cars such as the Camaro, Firebird, and Mustang. In construction, the cars are almost identical to Late Model cars, with tube-frame chassis and pla
Transfer Slot/Spot	In a race that uses heat races to determine qualifying for the feature or main race, the transfer slots are the finishing positions in the heat races that qualify the drivers who finish in those positions to advanced to the feature. Typically, this will b
Transponder	A small electronic box, attached at the same point in each car, that sends out a small signal every time it crosses a fixed scoring point.
Transporter	A large tractor-trailer used to transport racecars and parts to a racetrack. Those used by teams in the major series usually have the space to carry two cars (one above the other), spare engines, transmissions, and axles, and a small workshop complete wit
Traps	The two beams of light at the end of the drag strip which compute mile per hour.
Tread	The portion of a tire that comes into contact with the road.
Tread Depth	The usable thickness of the tread. Small pinholes, called depth holes, are placed in the tread so tread depth can be measured.
Tread Pattern	This refers to the groove design on the operating surface of a tire. Most patterns are molded into the tread at the factory, but a custom grooved tire is also said to have a tread pattern.
Tread Rib	The tread section that runs around the circumference of the tire separated by the tread grooves.
Tread Width	The width of a tire's tread.
Tread Wear Indicator	Narrow bands, sometimes called "wear bars," that appear across the tread of the tire when only 2/32 inch of treads remains. This applies to DOT type tires.
Triangular	A track has the tri-oval stretched out from the center of the track to the point that the track has three corners of nearly equal angle. At such a track, the dogleg is considered a numbered corner (unlike the other types of tri-oval, where the dogleg isn'
Tri-Oval	An oval track where the front straight is built with a dogleg (the word "tri-oval" is also the name used for the dogleg itself). The main advantage of this type of track is that, for fans in the front straight sitting around the curve of the dogleg, the c
Trip Strips	Small undulations on an open wheel driver
Tunnel	Underground entrance and exit to a tracks infield. Installed at many tracks to allow for smaller trucks and other traffic to access the infield without damaging or soiling the track.
Turbocharger	A device that uses engine exhaust pressure to drive a compressor, which forces more air into the engine, usually directly into the intake. See also supercharger.
Turbulence	Swirling, disrupted air.
Turn In	Location on the track where the driver starts to turn the steering wheel to enter the turn.
Turn Numbering	A numbering system that is used to refer to the individual turns of an oval. Since the typical 180-degree corners can constitute the bulk of an oval, they are split into two halves, which are numbered separately. Thus, the first half of the first 180-degr
Turn Out	Location on the track where a driver turns the steering wheel back for exiting a turn.
TUSA	Team United Sanctioning Association.
Tweak	Minor adjustments.
Tweel	Combination of the two words tire and wheel. A single piece product that serves as both a tire and a wheel. The Tweel features a network of polyurethane spokes fused to a wheel hub and a circular outer flat rim that replaces the casing, beads and sidewall
Two Hundred MPH Tape	Also known as "racer's tape." Highly adhesive Duct tape strong enough to hold parts of the racecars body together at high speed.
Tyre	Alternate spelling for
UARA	United American Racing Association.
UDRA	United Drag Racers Association.
UDTRA	United Dirt Track Racing Association.
ULMS	United Late Model Series.
UMARA	United Midget Auto Racing Association.
UMP	United Mid-Western Promoters. Sanctions Late Model and Modified racing in the United States.
UMRA	United Midget-Racing Association.
UMSA	United Mini-Sprint Association.
Understeer	A handling condition where the front wheels tend to slide when turning into a corner, which makes the car want to keep going straight. Also called push or tight. The opposite of loose and over-steer.
Undertray	A portion of the underbody of a car that is sculpted to increase downforce.
Un-Lap	When a driver down one lap passes the leader to regain their position on the lead lap.
Un-Sprung Weight	The weight of the wheel, tire, and suspension parts that are not supported by the springs. More un-sprung weight means more inertia in the suspension, which usually means less responsiveness and poorer handling, so reducing un-sprung weight is a major pre
URC	United Racing Club.
USA	United SprintCar Alliance.
USAC	United States Auto Club. This organization sanctions open-wheel racing including Silver Crown, Sprint, Midget, and Formula 2000 events from the Midwest to California.
USAR	United Speed Alliance Racing.
USCS	United Sprint Car Series.
USMTS	United States Modified Touring Series.
USOMS	United States Outlaw Mini-Sprint Association.
USRA	United States Racing Association. Sanctions weekly racing.
USTAR	Ultimate Short Track Auto Racing.
USTCC	United Stated Touring Car Championship.
UTQGS	(Uniform Tire Quality Grading Standards) A tire information system that provides consumers with ratings (from A to C) for a tire's traction and temperature. Tread wear is normally rated from 60 to 620. Ratings are determined by tire manufacturers using go
Valance	A panel that extends below the vehicles front bumper. This is used to divert air around the car and not allow it to travel under the car. This helps with increasing downforce.
Valve	A device used to start and stop the flow of a liquid or a gas.
Valve Core	This is the core of a valve stem. The core is depressed to apply or remove air from the tire through the stem. The core can be removed from the stem to increase the airflow.
Valve Float	What happens when an engine is run at an RPM higher than what the valve train is capable of operating at, resulting in the valves' failing to close completely during the compression stroke. Valve float causes loss of power and usually leads to engine dama
Valve Stem	An assembly, metal or rubber that houses a valve cap to keep out dirt and moisture and a valve core to prevent air from escaping.
Valve Train	All parts related to the function of the valves.
VARA	Vintage Auto Racing Association. Sanctions vintage road racing.
VARC	Vintage American Race Cars. Sanctions vintage car oval track racing.
Vent Hose	On an Indy car, the alternative to a catch can for recovering fuel that overflows from the fuel cell during the refueling process. The vent hose plugs into the vent port and takes the overflow back over the pit wall to a tank for measuring and recovery.
Vent Man	On an Indy car, the pit crew's member who handles the vent hose. This person also handles the air hose for the car's built-in pneumatic jacks.
Venturi	An area of a device that reduces area in order to speed up flow.
Victory Lane	An area on or inside the track where the winner is honored after the end of the race.
Victory Lap	A celebratory lap taken by a race winner, after the race is over. Generally, the driver will remove helmet or gloves and wave to the fans. Some weekly racing venues don't give out trophies for heat races or other preliminary events, so on such occasions t
VMRA	Vintage Modified Racing Association.
VNT	Variable Nozzle Turbocharger.
VOTRC	Virginia Old Timers Racing Club.
VSS	Virginia Sprint Series.
VTEC	Valve Timing and Lift Electronically Controlled.
Vulcanization	The curing portion of the tire manufacturing process when the tire is inserted into a press and heated to encourage polymer bonding and cross-linking.
VVT-I	Variable Valve Timing Intelligence. Refers to a computer controlled valve system rather than a hydraulically controlled one.
W	Can refer to an engine with its cylinders in a "W" configuration (three banks), but in the context of oval-track racing, this is usually understood to mean the Ford "Windsor" small-block V-8, which is a common alternative to the Chevy small-block in many
Walking the Dog	Describes a driver who was lucky enough to hit the proper setup and is running away from the field.
Wally	Trophy given to all NHRA National Event winners. Named for series founder Wally Parks.
War Wagon	A large pit cart usually stocked with all the necessary components to rebuild a racecar after a wreck. These carts become popular in most all-traveling series when access to the team's trailer during a race was limited, or when returning to the trailer le
Warm-Up Lane	A paved lane, separate from the racing surface, that extends from the pit exit to some point further around the track. The idea is to give cars exiting the pits a separate area for coming up to speed, before they merge back in with the race traffic.
Water Burnout	Process of spinning your tires in water to get the tires hot and sticky for better traction.
WCAR	West Coast Auto Racing.
WCS	Wisconsin Challenge Series.
WDRA	Western Dirt Racing Association.
WDRL	World Dirt Racing League.
Wear	The loss of material from a part due to friction.
Wear Bars	Raised sections of tread grooves that indicate only a small portion of tread depth remains. In race tires, wear bars usually appear at 2/16th of an inch of tread remaining. Applies to DOT type tires.
Weaving	Zigzagging across the track to warm up and clean off tires.
Wedge	(1) In Stock cars, the dynamic weight balance of the car from corner to corner using a jackscrew at each corner, attached to the spring mount; turning the screw transfers weight to or from that wheel, altering the handling characteristics. (2) Extra rubb
Weekly Racing	Weekly racing at most tracks consists of several classes of racing, some amateur and some professional classes. Generally, each class will run qualifying, heat races, and a feature.
Weight	A measured piece of metal usually lead attached to a wheel by tape or clamped on. Used to balance a tire/wheel assembly to reduce vibration.
Weight Jacking	The art of shifting a portion of the weight of a car to certain wheels or corners to improve tire grip and the cars handling.
Weight Transfer	The dynamics of weight being transferred. Side to side during cornering, to the rear wheels during acceleration and to the front during deceleration or braking.
WESCO	Washington Economy Sprints.
Wet Nitrous Setup	Injecting nitrous mixed with fuel.
Wets	Tires used during wet conditions. Usually grooved to channel water away from the center of the tire in order to have a good contact patch. Also referred to as rains.
Wet Sump	The type of oiling system used in most passenger cars, and in some racecars (usually the lower classes). In a wet sump, oil that isn't being used at the moment is stored in a sump, which is an area built into one end of the oil pan (under the engine), lik
Wheelbase	The length of a vehicle when measured from the center of the front hub to the center of the rear hub.
Wheel Hop	A hopping action of the rear wheels during heavy acceleration. Traction is lost and regained in rapid cycles after power is applied to the rear wheels.
Wheelie Bars	Bars attached to the rear of the car to prevent excessive front wheel lift.
Wheel Packing	Dirt terminology for using racecars to smooth the surface of a dirt track. Prior to a race night, most dirt tracks are dug up and watered. In order to level and smooth the surface, cars turn slow laps, often clockwise, to pack the dirt down smooth prior t
White Flag	A flag displayed to indicate one more lap remains in the race.
Wicker Bill	Also called a Gurney flap. A small spoiler-like tab that sticks up (or down) perpendicular to an aerodynamic surface, such as a wing; it has the effect of increasing air pressure on that side of the surface, making it produce more force in one direction o
Wicking	(1) Very slow loss of air pressure from a tire. (2) Process used in the manufacturing of tires to eliminate air pockets.
Wide-5	A wheel-and-hub system where the area that would normally be the center of the wheel is instead part of a star-shaped hub. The wheel itself has no center; the wheel's mounting holes are on small tabs protruding from the inside of the rim. Wide-5 wheels ha
Windmill	Another name for a supercharger.
Window Net	Tight webbing that covers most of the left-side window of a Stock car, next to the driver. It prevents the driver's head and left arm from going out of the window in a left-side impact or roll, and it keeps crash debris from flying in the window and strik
Windscreen	The windshield or a transparent fiberglass surface on the front of a car designed to aid airflow and deflect turbulent air from the driver.
Wind Tunnel	Controlled environment in which cars are tested against a generated airflow. Used to test and improve aerodynamic characteristics of a racecar and its components.
Wing	As used in auto racing, the object of the wing is to provide downforce to stick the tires to the track, as opposed to the aircraft use of creating lift. Early wings were aircraft wing sections turned upside down, but nowadays most are purpose-built for ra
Winglet	Name given to any smaller body wing or aerodynamic device.
Winners Circle	Located in Victory Lane. The location the winning driver takes his car.
Winston Cup	NASCAR's top Stock car racing series whose primary sponsor was RJ Reynolds Tobacco Company who manufactures Winston cigarettes. Prior to 1982, this was referred to as the Grand National division. Primary sponsorship was changed to Nextel in 2004.
Winston West	A NASCAR series in the western U.S., which uses cars similar to the Winston Cup cars. The series evolved from the old Grand National West series on the West Coast. Today, the cars are similar enough to Winston Cup cars that, prior to 1997, Winston Cup eve
Wire-to-Wire	A driver who wins the race from the pole position.
Wishbone	Suspension member that connects the wheels to the chassis. Named this because it is shaped similar to a turkey wishbone.
WKA	World Karting Association. Sanctions kart racing in North America.
WMRA	Washington Midget Racing Association.
WoO	World of Outlaws, a sanctioning body that sanctions Sprint car events across the United States. WoO cars are noted for their large wings (as opposed to USAC sprints, which aren't allowed wings).
Worst to First	When a car starts in the back at the beginning of a race and then wins in the end he is said to go from worst to first.
WOWMS	Wolverine Outlaw Winged Midget Series.
WRA	Western Racing Association.
Wrench	Slang term for a mechanic.
WRL	Welterweight Racing League or Western Racing League.
WSOA	Winged Sprints On Asphalt.
WTQMA	Winged Three Quarter Midget Association.
Xtreme	Late Model Dirt Car series formally known as the United Dirt Track Racing Association.
Yaw Angle	The difference between the direction the front of the car is pointing and the direction the car is actually traveling.
Yellow Flag	A flag indicating that a wreck has occurred, or some other condition (such as rain, debris, or spilled oil) has made the track unsafe for racing at speed. In oval-track racing, when the yellow is in effect, all cars must slow to a safe speed, and passing
Yellow Stripe	In many oval track series, a rookie driver is required to put yellow strips of tape on rear of their car. The purpose of this is to warn other drivers that they are approaching an inexperienced driver.
Yellow Tail	Slang term for a rookie driver. In most series rookies are required to have a yellow stripe on the back of their car.
Zig Zagging	Weaving across the track to warm up and/or clean off tires.

Roadkill Customs

DIY Hot Rod Tech, Tools, Rides & Lifestyle

Glossary of Racing Terms