Newbi question of the day: What is the typical piston to cylinder clearance, in diameter? Is it important to be the same for every piston is the engine?

What would be a reasonable factory tolerance vs a blueprinted engine tolerance?

Tx

 

I think it depends on the piston. The Arias Extreme duty pistons need more piston to wall clearance since they're zero silicon. I think .003 is the norm though but don't quote me on that because I'm not a mechanic either haha.

 

every piston manufacturer will include a clearance min and max card with their pistons. just shoot for the tighter tolerance and that is basically your blueprint spec. other things are factors though depending on the motor useage and time between rebuilds. measured at the piston top because the skirts (piston bottom) are designed to rub to hold the piston square in the bore and are oval shaped 90 degrees from the piston pin.