Dinan's lightweight billet aluminum crankshaft pulley underdrives each of the accessories by 13 percent, reducing parasitic drag on the engine for a 6 HP @ 8000 RPM and 4 lb-ft torque @ 8000 RPM gain on a stock vehicle. The Dinan underdrive pulley retains the factory harmonic crankshaft damper, eliminating vibration that might otherwise damage the crankshaft.
This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2006-2010 | BMW | M5 | Base |
| 2006-2010 | BMW | M6 | Base |
