Originally Posted by Kris Thompson
i have a sbc bored .60 over with flat top pistons and a texaes speed ms4 cam with a .649 .609 lift solid roller.. my question is can i run 305 double hump heads they have 2.02 valves my cam specs say to use shorter pushrods 7.425 length im not sure what stock is but they are shorter then the ones i pulled out of motor. i just dont want valves hitting pistons but i would like to have the compression and valves from those heads.
Solid roller p-rods are going to be a lot shorter than stock SBC (~7.8"). Exactly how long depends on a lot of things. If you know who's roller lifters you are using you can get close enough to the right length to start the geometry measurements to get the exact length needed.
is a list of valve train points to check.
I don't think those 305 heads- regardless of how much porting has been done- will ever support a solid roller cam w/that kind of lift and duration. The only thing they have going for them is a small chamber, but even they won't be so small once the chambers are unshrouded to let the 2.02" x 1.60" valves breath. The ports are just too small to flow at the lifts and RPM that cam is going to need to make power like it should. The engine will run, but it will not be anywhere near where it should be, power-wise.