This lightened crank pulley for the MINI Cooper S is CNS-machined from premium 6061-T6 aluminum billet, and maintains the stock diameter of the MINI Cooper while losing about 75% of the stock weight. At just 22 ounces, the reduced rotational weight of this lightweight MINI Cooper Pulley has shown increases in horsepower and torque across the entire RPM range of the MINI Cooper S (with maximum gains @ 4000 rpm).

The stock diameter of this lightweight crankshaft pulley does not affect reliability and does not contribute to increased wear, vibration or noise.

Under or overdriven crankshaft pulleys are not recommended however. Underdriven pulleys often result in drivability and electrical problems (undercharged battery).

Overdriven pulleys, especially coupled with reduced diameter supercharger pulleys, can result in poor performance, reduced fuel economy, compromised reliability and increased emissions. See our article on our NME5011 ULTRIK Supercharger Pulley Upgrade Kit for details.

See installation instructions here.