Raw GM crank forgings are shipped directly from GM to Crower. The stock GM part number is forged into the counterweight. Features include lightening holes and O.D. trimming that reduces weight by 4-5 lbs under stock. Crower race-prep includes 1/8" radii and Crower heat-treat. Thorough magna-flux inspection, chamfered oil holes, end-to-end index check and polishing come standard. Weight: 51lbs