Check the listing for details. AMG Mercedes M113k BLACK 77mm supercharger pulley E55, SL55, CLS55, G55 70HP +. Condition: New. Listed at 560.00 USD. Ultimate Performance supercharger pulley upgrade for the AMG 55 Kompressor motor. Our tests show 60 to 70 + rear wheel hp and torque gains, while maintaining a safe level of boost and supercharger rpm. Pulley upgrade offers excellent driveability and does not adversely affect highway mileage. Fits 2003 - 2007 AMG Mercedes 55K ModelsThe patented and original Ultimate Performance supercharger pulley upgrade for the AMG 55 Kompressor motor. Our tests show 60-70+ rear wheel hp and torque gains, while maintaining a safe level of boost and supercharger rpm. Pulley upgrade offers excellent driveability and does not adversely affect highway mileage. Specs:Increases horsepower and torque35% lighter than factory pulley, reducing rotational massReduced rotational mass increases supercharger longevity77 mm diameterEasy to installSpecial coating reduces belt slipImproved nitride coated clutch, plate and spring design 77 mm in size up to 3+ psi increase with tune (as compared to a stock supercharger pulley)Weight: 2.5lbs (one pound less than stock 3.5) ~28.5% reduction in weightEquates to 180mm crank pulley in power but much less rotating mass! Made in USA by UPD (not offshore)