The Edelbrock 122 Supercharger Kit part 1551 for 1955 - 86 302 - 400 CID Small - Block Chevrolets is a positive displacement supercharger that is capable of producing 500 horsepower on a small - block Chevy engine. This system utilizes the Eaton H122 rotor assembly for maximum efficiency in a compact package. The compact design may potentially fit under the hood of most muscle car and street rod applications. Testing resulted in a peak of 507 horsepower and 487 ft - lbs of torque 5 PSI on a 350 CID with 9.51 compression. The Edelbrock 122 is designed for use with factory style belt and pulley configurations. Will not work with aftermarket serpentine pulley systems and will require the use of a long - style water pump. Each kit includes the supercharger assembly with Eaton internals, intake manifold, drive pulleys, belt, gaskets and all necessary items for ease of installation. Does not include carburetor, so you can use your carburetor of choice. This Edelbrock supercharger is intended for 302 - 400 CID Small - Block Chevrolets equipped with long water pumps and stock style bracketry. It's designed to utilize the factory accessory drive belts, in conjunction with the secondary 6 - rib supercharger pulley drive system. Manifold height A - 8.50in., B - 9.75in. Carb pad height 9.125in. Satin Finish.