m5board.comoholic (>1000 posts)
Join Date: Oct 2006
Location: Dallas, TX
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To clarify, this is the scenario this weekend:
1. Classic BMW (a BMW dealer) had a "Dyno Day"
2. They use a Dynodynamics dynonameter (also used by RPI for example)
3. On Saturday, the 2009 CTS-V dyno'd and pulled 456 rwhp/450 rwtq
4. On Saturday, the 2008 Stroker M5 dyno'd and pulled 457 rwhp/330 rwtq (I posted an incorrect trq amount in the video)
Having done numerous dyno pulls now with my car I know it's making much more power on the road, so for grins me and the owner of the CTS-V decided to do 3 runs together. All 3 started at roughly 40-45 mph. My car has dyno'd 466, 500, 525, adn 557 rwhp at other times/locations/dyno types (mustang, dynapak, and dynojet).
I hope this helps to clear up any confusion. I made the video to show dyno numbers are extremely misleading in naturally aspirated cars without proper air flow. I am a firm believer now.
Forced Induction cars (Ford GT, CTS-V, etc.) are not impacted really on the dyno and show proper figures since the supercharger is forcing more air in regardless if the car is moving or not.
My Dinan Stroker M5 platform is predicated on having proper airflow (larger MAFs, larger air intakes, larger throttle bodies, larger displacement, etc.) and without real-world air flow my numbers are going to be way off.
Hope this helps to clear things up.
2011 X5M Carbon Black