[84grandprix]

i have a set that are pinned rocker stud comp cam roller tip rocker 1.52 ratio with comp springs what is the max lift cam i can use ? right now i have comp cams magnum12-242-2 280/280 480/480 with 110degree seperation.. i would like to go bigger they are on a 74 350 .040 all forged lower end i want to make as much power as i can out of the stuff i have.. i dont mind doing the work its fun :evil:

 

[SSedan64]

Those 3970126 have tiny 1.72" Intake valves, you're wasting your time.

 

[DoubleVision]

SS Called it right. The small 1.72 intake valve coupled with a smallish intake runner was made for high torque at low RPM. The powerband of these heads are over at 3500 RPM.