How many 302 heads do you see deep in the 10's in steel door cars on all throttle and stock stroke??? I can tell you I've seen of X/J heads deep in the 10's
My machinist use to run a bare bones low comp 8-1 318 right down to stock rod bolts in a light car that used to run 11.0s and they had to swap out the air gap for a lowly performer to slow the car down because it would have broken out of the class limit.
