Once the temperature in the shop gets a little more friendly, I'll drag out the CC tester and do a comparison of combustion chamber volume on an 848 head compared to some of the other casting numbers. From there, it's pretty simple to calculate static compression ratios using such info as cylinder volume, piston deck height, head gasket thickness, etc.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!