The perfect addition to a set of MBH long tube headers. This 77mm supercharger pulley is the equivalent of running a 180mm crank pulley on your 55 Kompressor AMG, without the drawbacks of a larger crank pulley. Expected gains of 70+ wheel horsepower!
Running a 77mm supercharger mounted pulley over a large crank pulley like the old 180mm offers many welcome benifies. You get all the power without the added rotatrional mass. In turn it means the 77mm supercharger pulley will actually make more power becasue its not fighting against its own size and weight. Your 55 Kompressor will also rev faster as the engine doesnt have the added bulk of a larger crank pulley to spin. 
Benifits of the 77mm Supercharger Pulley over a Larger Crank Pulley
More horsepower & torque
Less rotational mass
Faster engine revs
Lower engine temps
Better gas millage