CVF Racing Ford Big Block V-Belt Crankshaft Pulley. Pulley provides 95% underdrive ratio when used with CVF Racing water pump pulley. Designed for use with stock power steering and alternator brackets. Intended for vehicles with power steering and alternator. Fits vehicles with factory 4 bolt fluid dampener and 1970 or newer water pump. Dampener face to water pump flange face 3 1/16"