Piston compression height is the distance between the centerline of the pin to the flat part of the top of the piston. It's important to know this number when ordering pistons--especially custom ones- ...

You'd think that the pistons listed for a 10.5:1 compression ratio would actually give you 10.5:1. But it's usually not that simple. Perhaps that's why so many four-wheelers have a foggy or incomplete ...