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vichang4 vichang4 is offline
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Join Date: May 2003
Posts: 132
Quote:
Originally posted by camgrinder
Victor, You need to calculate intake valve closing point in your effective compression formula. The later you close the valve on the compression stroke the less swept volume you will have for your formula.
I agree that changing the cam will affect compression ratio. For my rebuild, I'm staying with the stock cam and I'm using the formula to calculate effective compression ratios at different boost pressures and different compression pistons. My conclusion is with the 7.5 to 1 pistons I need to back off of the boost from 1 bar to .8 .
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Victor Toce
2000 Boxster S w/
Tequipment exhaust
1993 Spec Miata
87 911 turbo - sold
3.4 RUF pistons and cylinders
Euro CIS head
Old 04-08-2004, 05:51 AM
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