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      05-30-2020, 02:36 PM   #23
Earlando86
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I'm as proud as the next M5 comp owner to read this. But I've never seen details of the 2.6 stock run anywhere. Wonder if it's a mistake...
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      05-30-2020, 02:49 PM   #24
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can you prove that?
Usually a RWD Porsche has a drivetrain loss around 8%. No way an AWD platform is the same. I could see as low as 15% but not half that. Open to being wrong but seems unrealistic.
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      05-30-2020, 10:21 PM   #25
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Drivetrains are extremely efficient these days. Loss is likely 7-8% not 12-20% like 10-15 years ago
can you prove that?
I've read in numerous places how drivetrain loss is significantly mitigated these days.

Either way it's known that BMW obv underestimates power.

I saw MT did do a Dyno test on 992 C2S 414 whp and 406 wheel lb ft. based on wheel hp also significantly underrated

In the article MT calculates 15% drivetrain loss. I think that's high


https://www.motortrend.com/news/2019...a-s-dyno-test/
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      05-30-2020, 10:23 PM   #26
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Quote:
Originally Posted by Funf6cyl View Post
Quote:
Originally Posted by Higgs Boson View Post
can you prove that?
Usually a RWD Porsche has a drivetrain loss around 8%. No way an AWD platform is the same. I could see as low as 15% but not half that. Open to being wrong but seems unrealistic.
The C2S and C4S 992 have same engine and put down same wheel Dyno numbers. This would suggest similar drivetrain losses. If drivetrain loss were more the 4S would register less wheel HP it doesn't from all Dyno charts I've seen on Porsche boards.

MT did Dyno test on 992 C2S wHP was 414 and wheel lb ft 404 they used 15% drivetrain loss and calculated crank HP

Then again they dyno'ed a claimed 450 HP GT3 at 390's so who knows as the 992 S has less claimed HP but hit a much higher whp than the GT3

15% drivetrain loss seems high


https://www.motortrend.com/news/2019...a-s-dyno-test/
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      05-31-2020, 02:37 AM   #27
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Quote:
Originally Posted by Neptune7 View Post
I'm as proud as the next M5 comp owner to read this. But I've never seen details of the 2.6 stock run anywhere. Wonder if it's a mistake...

This was also the first I heard of the M6 Comp doing 2.6.

Correct me if I am wrong, some car magazine had tested the two and the non Comp actually had faster times by a smidge, could have been choice of tires.
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      06-03-2020, 10:14 PM   #28
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Quote:
Originally Posted by LSM View Post
The C2S and C4S 992 have same engine and put down same wheel Dyno numbers. This would suggest similar drivetrain losses. If drivetrain loss were more the 4S would register less wheel HP it doesn't from all Dyno charts I've seen on Porsche boards.

MT did Dyno test on 992 C2S wHP was 414 and wheel lb ft 404 they used 15% drivetrain loss and calculated crank HP

Then again they dyno'ed a claimed 450 HP GT3 at 390's so who knows as the 992 S has less claimed HP but hit a much higher whp than the GT3

15% drivetrain loss seems high


https://www.motortrend.com/news/2019...a-s-dyno-test/
I’ve seen the 992S dyno there. Using the 8% drivetrain loss on a RWD 911 it puts you exactly where it should be (447).

I think Akra did a dyno on the 4S and got 396 WHP, which at 12% puts the power at 444 crank. Those are ways the numbers I’ve typically held for Porsches. Porsches also tend to be much more efficient in their power, which is typically why they overachieve for relatively small hp numbers (I.e. 992S runs 11.2@125).

The GT3 numbers are weird. They usually dyno high.

I’d also love to know what gear they used for each dyno.
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