piston to valve
#2
TECH Resident
The standard for race motors is minimum .080 intake and .100 exhaust. I would be surprised if it was any less than that. But, I have been surprised before, and everyone has a different opinion about how much clearance you really need. If you have ever been at WOT when a piston kisses a valve, you will learn real quick about why clearance is important. I always ask for more than .100 when I buy pistons.