Piston to Valve Clearance

[racerdude5]

On a Small block Mopar, with 302 heads and stock valves. Let's assume the deck height is factory at 9.6 inches and the piston to deck clearance is .067 inches. The heads have not been milled at all either. We'll be running head gaskets with a compressed thickness of .03 inches, making our total piston to head clearance .097 inches. With this clearance from piston to head, what is approximately the maximum amount of lift I can run on my can (for both intake and exhaust)? And at what amount of lift, will I need valve relief cuts in my piston?

 

[krazykuda]

The only way to check piston to valve clearance is to put it together and check it.

Too many stack ups and unknowns to do "with book numbers", it's a waste of time to generate a number that won't mean anything anyway. You have to check your parts to see where you are. You have no way to know if the heads and block have been decked and where they are.

 

[RustyRatRod]

The lift is not the critical measurement. You need to be more concerned with duration. It's not how much, but when and how long the valves open that matter. As said, the only way to tell is choose a cam and set it up and find out.

 

[70aarcuda]

as said..max lift is not your problem...at max lift the pistons are no where near the top of the cylinder...As Rusty said...duration...and especially during the overlap period where the exhaust valve is closing and the intake is being to open...the piston is near TDC....

how about posting the cam specs.....