Thread: Ims rpm
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Old 07-11-2014, 09:13 AM   #4
thstone
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Join Date: Nov 2010
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I have found these references saying that the stock crank pulley circumference is 454mm and the alternator pulley circumference is ~166mm (taking the 53.9mm diameter and converting to circumference). This would give a ratio of ~2.7:1.

This was the best that I could find.

Mantis versus BBI pulley size

Amazon.com: NEW ALTERNATOR PULLEY PORSCHE 911 SERIES BOXSTER 0-124-515-073 996-603-012-02: Automotive
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