I'm running a 431, 440 crank in a 383 .030 over block. 11:1 forged pistons, ported 906 heads with stock valve size, .580 lift solid flat tappet cam, 3/8 push rods, 440 source rockers, erson dual valve springs, dual 450 cfm holleys, hooker super comp fenderwell headers, and she is comfortable at...