Thread: M3 Dynotest
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      09-08-2007, 11:23 AM   #10
lucid
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Quote:
Originally Posted by GregW / Oregon View Post
Why do you suppose peak power on the M3 was measured at 7,808 rpm vs. 8,300 as spec'd?
Tranmission losses are non-linear. Meaning, the %loss might be higher @8300 than @7800. They actually did not go above 8100 in the test. I downloaded the whole sheet, and here are the details:

@7808: 377.9 hp; 340.0 Nm
@8108: 377.8 hp; 327.6 Nm

It seems like they were taking measurements at 300 rpm intervals and stopped once Tq started dropping seriously and Hp kind of leveled off. I still would have like to see a datapoint at 8300 though.
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