i was just wondering. thanks.

 

compression ratio does,but the cam size dosent!! if you would like a detailed answer just give me a shout....

 

yes, basically anything that significantly affects cylinder filling can affect compression test numbers. Though the slow speed of the engine cranking will show very litttle effect from most cams (they'd have to be gigantic), varying static compression ratio will show a marked change in peak numbers.


[Modified by texan, 1:07 AM 10/19/2002]

 

so the cams won't affect static compression, but will they noticeably affect the compression when the engine is actually running?

 

cam size AND cam timng will effect cranking compression numbers. Just changing the cam timing can effect the cranking compression numbers by over 20%.

Numbers for thinking
D16 with stock cam at zero, 200 psi across the board
same setup with cam at 2 degress retard, 180 psi
4 degrees retard and I got 160-165 psi cranking compression numbers.

 

Yeah, I'm thinking the same thing as Mista Bone. When I did my compression test the first time, my cams were set at +3 degrees (intake) and the numbers were close to 230psi. Now with them set at +1 degree (intake) the numbers are closer to 220psi.

 

is the stock setting 0 and 0

 

Yes, for cam timing.