[DeTomaso] Compression ratio question

[Dagny Kristine Bakken]

If i understand it right,the compression pressure in a fresh engines
cylinder is the result of compression ratio + eventually charging from the
intake air , minus pressure escaped from bypassing pistonrings,minus
pressure lost from the cams exhaust overlap to help get rid of the exhaust.I
understand that the rpm. and thereby the airspeed will affect this,but how
much?
One thing i know for sure ,is that its very important to have the throttle
wide open when measuring the compression pressure,as you otherwise build up
vacum on the intake side and get wrong result :)
 
Øyvind Bakken