Not to hijack but I have dyno tested two different sets of heads that flowed 30 CFM different with every thing else the same, compression, camshaft, intake manifold carb, but not the same rocker arms due to testing a set of Indy SR M.W. that flowed 340 CFM @.700 lift and then a set of CNC ported 440-1 that flowed 370 @ .700 lift. I had Harland Sharp 1.6 ratio rockers on both sets of heads, I tested both sets of heads on two different short blocks and the bigger heads made 48 HP more on the pump gas 518 C.I. low deck stroker(727 HP with the SR and 775 HP with the 440-1) and they made 70 HP more(775 with the SR and 845 with the 440-1) on the high compression 526 C.I. RB motor.
IHTHs