Kit includes a machined aluminum double groove water pump pulley and double groove crank pulley, and a matched pair of heavy-duty belts. Has a 1:1 water pump/crankshaft speed ratio.Heavy-duty aluminum constructionMatched V-belts - 30-5/8" x 3/8" belts1:1 to ratioFits Small Block Chevy V8 with '55-'68 short-style water pump with either a 5/8" or 3/4" shaft.Note: The lower crank pulleys in these combo kits are manufactured thicker than normal stock pulleys. This requires longer 3/8" bolts to be purchased separately. Allen head type bolts recommended.
