A bunch of chev guys think that my p79 that I shaved .080 will need valve releifs cut into the pistons (flat tops) if I want a hot cam. I've never heard of anyone having to do this here, am I exempt from this??
I heard .500" is max lift without fly cut. I ran p79 with .040"-.060" shaved with .480"lift cam (fel-pro head gasket) with about .080 plus .040 extra valve clearance btw pistons and valves. I also had my valve seat shaved so I had extra clearance. (valves sat further from the pistons) To check the valve and piston clearance, you need play-do.....seriously. put the engine together with headgasket and everything in place (well, crank, bearings, pistons, rods, and things) put the play-do on the top the piston and place your head with the new cam and springs. turn the engine over manually one or two rotation to get the in print of the valves. take the head off and peel off the play-do. measure the thickness of the play-do with micrometer. you need .080" for intake and .100 for exhaust I think.
Well, it's been a while since I played with the stuff.. should be fun
My real dilema is that I have a choice of 2 cam grinds that the guy dug out of a back shelf, and one is like a 260 and the other 280 dur., but he can't tell me what lift!!! Other than that, it's out of country, and the exchange sucks for me right now!! 1.63 is what I pay for one american!!!