Thanks for the answer, I had one reground some time ago for a 318 and the guys at oregon cam had never seen a factory billet at that point. Anyway I did some research on the drive and nobody including the dealer could say for sure if it was a different gear. There was a part number change in 1992 so some speculated it was due to increased wear with the billet but the magnums are cast. I just put the factory gear back in (that was mated to the billet roller) and it was good to go.
