*** IN STOCK SHIPS TODAY *** SBC crank hub made from billet heat treated steel, has one .250" and one .187" keyway 180 degree's apart. Uses six .375" bolt holes on a 2.782" bolt circle with an 2" pulley register and is made to work with 4-71 thru 14-71 roots superchargers.
This hub is for all internal balance SBC engines including 283, 302, 327, 350 and many more. Hub measures from pulley mounting surface to crank gear 2.350". Hub does includes a piece of timing tape.
RBS can provide a 7in. bolt on degree ring for additional cost #2300-0032.