We tried to DIG UP a 1955 Chevy Gasser that had been lying UNDERGROUND for 50 years! And we save the barn fresh 409 Chevy engine that powered it in the 1960s.
The 409 W-motor was the barn find of a lifetime, and as we found more history on it, we learned that it was in a 1955 Chevrolet drag car.
The car was wrecked, and the owner buried it in his backyard. After talking with the family, we went on a scavenger hunt to find the remains of the buried ’55 Chevy.
We found a corner of the cowl sticking up out of the ground, and the rest of the car was underground. It was a crazy idea, but we had a lot of fun with it…YouTube Channel Blown ’64 Vette
Unearthing A Legend
We eventually rebuilt the 409 engine in a three-part tech article series called “Unearthing A Legend” in Super Chevy Magazine back in 2014.
June 2014 Super Chevy: https://amzn.to/2Fa3Np6
July 2014 Super Chevy: https://amzn.to/2Y4b1DA
August 2014 Super Chevy: https://amzn.to/2FkTsYN
About the Chevrolet 409 Engine
The casting number on the rear of the block (409 casting number 3830814) tells us the engine would normally be found in a 1963 Chevy Impala. Like most Chevy blocks, the stamping pad is located on the front passenger side of the engine. As we scraped away the gunk and paint from the area, we couldn’t find any numbers or letters—nothing at all. That told us this block had either been decked or it was an over-the-counter block.
To get our answer, we rubbed muriatic acid over the stamping pad, as that can usually show the codes, even if the block has been decked. At this point, we still had not disassembled the short-block, so we did not have proper access to measure the deck height to double-check.
After all of our theories and testing, we determined the block was an over-the-counter purchase, direct from GM. We would later find out that this block was purchased from Dyno Don Nicholson, a famous Super Stock drag racer, who ran 409’s in the early 1960s.
Despite some advice to have the block bored (regardless of the condition of the cylinders), we kept the original bore and will utilize the original 11:1 forged pistons. We know the heavy original pistons are not ideal for today’s high-performance applications, but the fact that all of these parts were usable gave us enough reason to give up some horsepower.
Although the bottom end is stock, we updated the engine with a set of Edelbrock Performer RPM aluminum cylinder heads. These heads are half the weight of the original iron castings, and the ports are designed to flow 273 cfm (intake) and 216 cfm (exhaust) at a 0.600-inch lift.
The cylinder heads have the stock valve sizing of the popular “690” heads, which were used in 1962 and 1963 high-performance 409 engines—intake valves measure 2.19 inches and exhaust valves measure 1.72 inches.
We ordered the Edelbrock 60815 heads, which came complete with valve springs designed for a hydraulic roller camshaft. This brings up another way of updating our barn-fresh 409 to modern standard—a hydraulic roller camshaft and valve train.
We called the folks at Comp Cams to help us determine the appropriate profiles for this engine, making sure to have all the horsepower ramped in before our rpm ceiling of 6,000.
The end result is a camshaft with 236 degrees of duration on the intake side and 242 degrees on the exhaust side at 0.050-inch lift. Maximum lift is 0.578/0.593, which is right at the limit of our valve springs.
We used Comp Cams’ retro-fit link bar roller lifters (PN 8959-16), as they are a direct drop-in product with no modifications necessary. We added a set of Comp Cams Ultra Pro Magnum roller rocker arms (PN 1620-16), which feature a chrome-moly construction and a 1.7:1 ratio.
To button up this W-motor, we opted for dual quads, because it only seems natural on a high-performance 409. We used Edelbrock’s Performer RPM large-port intake manifold and a pair of Edelbrock Thunder Series (1803 and 1804) carburetors.
Chevrolet 409 Engine Parts Used
- Edelbrock Performer RPM Aluminum Cylinder Heads: https://amzn.to/2TGSAq2
- Comp Cams Roller Lifters: https://amzn.to/2Fk2a9I
- Comp Ultra Pro Magnum 1.7:1 Rocker Arms: https://amzn.to/2udm9Ai
- Edelbrock Performer RPM Dual Quad Intake: https://amzn.to/2TOOM6b
- Dual 500cfm Four-Barrel Carburetors: https://amzn.to/2Ob6Lh6
- Edelbrock As-Cast Finned Aluminum Valve Covers: https://amzn.to/2Y6yCDV
- Edelbrock Aluminum Water Pump: https://amzn.to/2FdZqte
- Pertronix Billet Distributor: https://amzn.to/2FktZhX
- Hooker 1-7/8-inch Super Competition Headers: https://amzn.to/2FlRcjW