Nicks Garage 383 build

The SD 455 was hampered by a 8.4:1 CR....& cam. Pontiac wanted to run the Ram Air 4 cam which was pretty stout for a production car, 231/240 @ 050 & had over .500" valve lift....but failed 1973 emissions. A milder cam was installed...& lost power. I believe it did 13s with the RA4 cam, showroom stock, the only production 'muscle' car to do so in 1973-4.
In production testing, the tq/hp went from 477/404 to 524/451 with headers & a tight 105 LSA RA 4 cam. With a Holley carb replacing the QJ it lost 13 ftlbs @ gained 12 hp, 511/463.

When the CR was increased to 11.9:1, the numbers were 574/530.