Mallory 29421PD Distributor Gear (Ford, SB V8, Predrilled) .531 inch diameter shaft CNC machined from alloy steel to Original Equipment specs and heat treated for maximum strength and years of trouble free service Perfect for 302, 351W, 3.8L and V6 Fords Designed specifically for cast flat tappet hydraulic and mechanical camshafts Pre drilled for the included roll pin Made of alluminum silicon bronze alloy Highly durable Precision CNC-machined