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polizei polizei is offline
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Join Date: May 2007
Location: Collegeville, PA
Posts: 1,369
Quote:
Originally Posted by lindy 911 View Post
What cams are you using?
Stock 3.2 Carrera cams

Quote:
Originally Posted by AlfonsoR View Post
How is the shop determining 80psi. Do they do 5 cranks or do they just turn it until it levels off?
I'm not sure. The test was performed by a very reputable mechanic with 30+ years experience. He said he ran the test multiple times because the results were so negative.


Quote:
Originally Posted by AlfonsoR View Post
What should it be with 8:1 and 3.2 cams? If the CR is really 8:1, then I'm calculating it should be right about 100 psi. (14.69 x 8) - 14.69 = 102.8 psig. This is purely a static calculation. If you have significant overlap, then that may explain why you're at 80.
I thought compression ratio had no impact on the amount of pressure that a cylinder could hold?

Quote:
Originally Posted by AlfonsoR View Post
Also, how sure are you about stated CR, i.e. did you measure?
No measurement was performed.
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Andy - 1987 911 Carrera Coupe
Old 01-09-2012, 05:08 PM
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