At first glance, the concept of engine compression is simple enough:It's the ratio of the volume of the combustion chamber and bore when thepiston is at bottom dead center (BDC) versus when it is at ...

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 ...