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      03-02-2013, 04:04 PM   #26
Boss330
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Drives: F10 5xxi N53B30 - AC Schnitzer
Join Date: Mar 2012
Location: Norway, Scandinavia

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Compared to this dyno (also done on a MAHA dyno) the numbers are odd:



The "Supersprint car" achieves 500whp and the "PP car" achieves 475whp. The car with only an exhaust makes 25 more whp than the PP car.

The outside temperature is at around 30 degrees on both cars, but the intake air temperature is 25 degrees on the Supersprint car and a whopping 72 degrees on the PP car. Indicating that the temp. sensor is either placed at different locations or that there has been terrible heat soak on the PP car... (see my previous post about the importance of temp etc when calculating crank horsepower on a dyno).

Corrected crank horsepower for the Supersprint car is 604hp (from 500whp)
Corrected crank horsepower for the PP car is 640hp (from 475whp)

The PP car apparently makes 40 more hp at the crank from 25 less hp at the rear wheels... (the reason for the high hp number on the PP car being the correction factors being so high due to the extremely high intake air temperature).

If I was doing a dyno run I would not have done it with a intake air temperature of 72 degrees (indicating a very inefficient intercooler or heat soak). The Supersprint dyno plot actually indicates a really efficient intercooler as the intake air temperature is lower than the outside air temp.

Would be interesting to hear why the intake air temperature was so high on the PP dyno and why it was so much higher on the tuned run than what it was on the baseline run. If the tune makes the intake air temperature rise that much (due to higher boost and more heat build from the turbos) then you loose any gain from the tune by the high intake air temperature. Meaning that you will not get more than 475whp when the Supersprint car gets 500whp...