RBS stocks brand new helix cut steel gears for large shaft roots blowers. These gears fit 6-71 thru 16-71 superchargers with 1.125" 48 spline shafts.
The drive gear has the standard six bolt 5/16-24" bolt pattern with the 1.50" register on the gears. Gears will fit most all other roots superchargers that use 1.125" 48 spline shafts in the rotors of the supercharger.