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      09-27-2012, 06:48 PM   #313
No 55mph
1QuikWS6's Avatar

Drives: 09 E92 328iX N51 3-Stage ->M6
Join Date: Jul 2009
Location: Blitzburgh, PA

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Originally Posted by CombatNinja View Post
What car is that dyno off of? The graph looks weird for a N51/2

More torque than power and only 168whp? What gives?
Don't confuse dyno data (RWHP/RWTQ) with BMW reported specs. Car manufacturer's report Engine HP/TQ - not at the wheels, so their ratings are always higher than what the car sees when the rubber meets the road

Normal drivetrain losses can be between 15 & 19% by the time the power gets to the wheels depending on type of DT (Man/Auto/RWD/AWD) so dyno results are more realistic.

HP is a number derived thru calculation using actual dyno measured Torque:

Power [HP] = T [] . RPM / 5252

Torque is the static measurement of the how much work an engine does while power is a measure of how fast the work is being done. Since horsepower is calculated from torque, what we are all seeking is really the greatest possible torque value over the broadest rpm range we can get. Different combinations of torque and rpm can yield the same horsepower. Therefore a slow revving engine needs a high torque to produce the same amount of horsepower as a fast revving engine.

Of the different type of dyno's available - the Mustang Dyno will always yield lower results over say, a Dyno Jet due to how it loads the car in real time, and lends itself to be a closer simulation to actual driving. I always have my Trans Am dynoed & tuned using a Mustang Dyno
2009 328ix E92//SGM//ACS Roof Spoiler//MTech Aero Lip+Trunk Spoiler//M3 Side Skirts//CF Roundels+Grilles//M3 Novillo Interior//Perf Shift Lever+Boot//MPerf DCT Wheel//M3 GT3 eBrake Handle+Boot//ACS Pedals//M3 Mirrors//LCI Tails w/LUX Rev//LUX 160 AE+MTec 6000K D1S+HPB HID 6000K Fogs//HPB LED Interior//RPI Scoops//CF Euro Airbox+Underhood Hsgs//K&N//BMW PE//MTech Rear Bumper-iS Sport Diffuser//CF Strut Brace//AA Stage3//BMW 193M's+Kumho 4X

Last edited by 1QuikWS6; 09-27-2012 at 07:01 PM.