im using p30 pistons on a b18a1 . so what would be the piston to deck ???

 

That will depend on deck height, has it been decked?
Head Gasket thickness, etc.
Here's a decent guestimator
www.zealautowerks.com

 

It's always better to measure it. If you don't have the tool, you can use a dial indicator. Once you get it TDC, rock the piston fore and take measurements at the intake and exhaust side of the piston. Rock the piston aft, and do the same thing. Then average those numbers out. Then you can decide if you need to deck it to get the compression you are looking for with what gasket thickness is available and make sure you have proper piston to head clearance. You really need to measure it rather than ask someone, or rely on a "calculator".

 

ok thankx for the info

 

all i did was resurfaced the block n head