Hey Fellas,
Correct me if I'm wrong, but I seem to remember that conrod length was the same for all SB in that era and various displacements were achieved by piston pin heights and crank stroke.I think the PowerPak heads were first used on the '56 or '57 injected Corvettes and by using these heads, a Crane "Fireball" cam, extractor headers and a Quadrajet carb on the 307, you get a nice high-revving engine without a lot of expense. Just my 2c.
OLD 42
