Thread: So how much dynamic compression are you guys getting away with on street pump gas?
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Old 05-19-2005, 06:55 PM
Excaliber Excaliber is offline
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Default Tricky stuff nailing down the NUMBERS!
9.8 static C.R. with a 282S Comp Cam.
7.9 Dynamic C.R., more or less. The numbers are HARD to nail down!

I'm not sure about the size of the head gasket "hole", I rated it at 4.4" 'cause it's not actually "round" you know! I'm also not sure of the head gasket thickness which I rated at .050 based on measuring my OLD head gasket.

428 rod length 6.490? 428 crank stroke 3.980. MY 427 bore worked out to 4.252 (.019 over). Piston Deck height, as I recall it was .005? -17 cc dish on the piston and 72cc chamber (I CC'd that ). Cam lash? Dang, thats a tough one to calculate!

Cranking Comrpression (gauge) is 210 psi. Runs great on 92 octane and finishes the 1/4 in the 11 second range. According to to PKellys site 7.5 to 8.5 is acceptalbe for a street engine.
Last edited by Excaliber; 05-19-2005 at 07:01 PM..
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