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ChrisBennet ChrisBennet is offline
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Join Date: Aug 2001
Location: Nashua, NH USA
Posts: 8,164
Garage
Quote:
Originally posted by KobaltBlau
M64 (factory 3.6) ran 11.3 (not 10.4) with twin plugs, BUT also had knock sensors and smart engine managment, that probably would retard the ignition if knock was detected (this is how it's usually done, but I don't know the engine managment well enough to state with 100% confidence)

what are your pistons?
Yes the factory compression figure for the 964 motor is 11.3.
However, when you actually measure it, you get 10.4.
Other Porsche motors have the same discrepancy.
For example:
A US 3.2 is ~9.2:1 not 9.5:1.
A 3.3 Turbo is 6.5:1 not 7:1.

-Chris
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Old 05-26-2004, 10:46 AM
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