I might be going from a 230/232 111+1 to a 230/236 112+ 2 since the cam has to come out. I really doubt I'll gain anything, but my heads are milled .015 and I don't want to get close to slapping a piston. Since the intake duration will stay the same but the exhaust gets slightly larger, I wanted to make sure that generally the exhaust valve isn't a worry when it comes to P to V clearance. Is this true at all?

 

It's generally the intake valve that will make contact.

 

check clearance, don't mess around or try to guess.

 

My exhuast valve was hitting first. With this new cam I am putting in there now. The exhuast duration is 242 with .50" milled heads. I had to flycut .170". Thats hella deep.

Always check to be for sure it will clear. You should have .100" to be safe.

 

I too have heard that it's teh exhaust thats in the most danger. But flycutting a stock piston .170 is pretty ballsy. How thick are the piston crowns?

 

The exhaust valve is coming down as piston is coming up, intake valve is chasing piston. The exhaust would be first to hit on an over-rev.

 

Is it even a good idea to flycut a stock piston?

 

At some points just over .250 I believe....

Yes if you miss a shift at HIGH rpm the piston is racing up the cylinder faster then the exhaust spring is closing the valve....