That MP number is way conservitive. The intake valve is opening from a rested seated position chasing the piston down the bore at its closest clearence.

You could probably go as tight as .020 and never have contact. I wouldnt go any tighter then .050 to .060 You will be fine with a .080 or .070 depending how far you want to mill your heads.


You still need to check your radial clearence. So far some has stated the 6 pac pistons are clearenced for 2.14 valves and some say they arent. Or was that you? Thats still up in the air for me, cause I dont know, mike