Keep in mind when you mill the head two angles change that are a problem - the first is the intake manifold to head angle most times the gasket just pinches and seals anyway but the two angles are now different, we cut to correct - the other angle only real shops will check is the one you asked about, the valve recessions in the pistons has now changed its location as it is in the relationship to , the center to center of the valve to valve pocket on the piston and that has to be checked, i am assuming the motor has performance stuff so intake / exhaust out side edge to out side edge of the pistons valve pocket is the deal to look at, you need .060 so again assuming your piston clearance is around .005 the piston in the cylinder rocks upward and out and that is the distance we have to cover with what your doing, very loose race motors need even more or motors that rev real high and run hot, and the .080 intake and ,100 exhaust is some what in the ball park more is better but sometimes you cant get their -- if you need a better explain i can re try but if you have done this sort of thing before you get it -- put the motor together using checker springs on #1 and 6 i think Pontiac and use a degree wheel between 5* and 15* on over lap , thats the real way - anything else is a bent valve waiting to happen -- i am in the middle of writing an article about degree a cam the correct way with simple tools if you have time it will be on soon -- jz
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