So performance starts at 10 secend et'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.
9-1 from memory. Cam was only 490 lift it was a long slow lobe.