[Bob Mulry]

Hi,

It's the large total volume (BDC) forced into the small volume (TDC).....

The reliefs and the domes make up the total volume at BDC and TDC after that it's just division to come up with the CR...

Subtract the reliefs and add the dome to a flat top for the correct number and don't forget the gasket thickness and bore diameter of the gasket..

Bob