Hub has the industry standard 2.00" pulley register, uses six .375" bolts on a 2.782" bolt circle for the blower pulley and measures 2.140" from crank gear surface to blower pulley mounting surface. Crank hub is double keyed with one .250" keyway and one .187" keyway a hundred eighty degrees a part to insure the crank hub stays where it needs to on the crankshaft.
Seal diameter on the hub is 2.125" designed for the LS timing cover. Crank hub will not seal on a RCD LS gear drive cover.
The hub includes a piece of timing tape but RBS can supply a degree ring at additional cost if the customer desires.
Crank hub is for internal balance engine and is black oxide finish. Degree ring part number is #2300-0032 if buyer chooses to purchase.