[63corvette]

My 434 with the Brodix 23 degree heads that made almost 850 HP on the dyno was a 14.8 to 1 compression ratio. Comp Cams small base circle with almost .800 lift. (1.5 & 1.7 Ratio Rockers)
It made its HP from 5400 to 7200 RPM
It was all in the flow of the Heads and manifold that Ron's Porting Service did. He actually cut the heads to about 21 degrees.
They flowed 440 CFM and I had to use a worked Gary Stinnett 1050 Holley to get it to work. I started out with a 950 and that just was not enough. The engine would just labor. When I changed carbs it really came to life.
The car weighed 2435 with me in it and would run 8.70's at 155 to 160 at sea level.
My 2 Cents