Competition Cams 4798 Crankshaft Socket for all Ford, Buick and Pontiac V8s For Ford, Buick and Pontiac V8 (Will not fit Buick 455) 1.385 inch ID with 3/16 inch and 1/4 inch Keyways Specially designed 1/2 inch drive socket allows rotation of engine assembly Knurled retaining nut that holds degree wheel in place Can be loosened while on crank snout so that wheel can be turned independent of the engine when finding TDC