BBC Engine Builder Specs

The Big Block Chevy (BBC) engine has a history that began with a bang--or at least a lot of excitement. In 1963, the Chevrolet team showed up at the Daytona 500 track and proceeded to blow the competition away. Their secret weapon was a big block engine that had a displacement of 427 cubic inches. On that day, a legend was born. The builder specs of the BBC engine help explain why it is still a force to be reckoned with.
General Description
The BBC engine is a V8 with a displacement of 540.7 cubic inches.
Bore, Stroke and Compression
The bore of the big block is 4.5 inches, while the stroke is 4.25 inches. The compression of the engine is 9.90:1.
Clearance
The clearances of the Chevy big block are tight: the main bearing clearance is .0025 inches, the thrust clearance of the crankshaft is .0065 inches, the rod bearing is .0022 inches and the rod side clearance is .018 inches.
Valve Spring
The seat pressure of the valve spring is 142 pounds at 1.940, the open pressure is 402 pounds at 1.250, and the coil-bind is 1.130.