I have some front drums (70GS) that I am putting together on some OPGI hubs. This item I bought used here and I put the drum on the hub and the drum holes are bigger than the studs. The shoulder doesnt go that far enough to press into the drum. I checked the hole in a stock hub/drum I have and they are the same as these replacements. My Napa has the correct studs (GM 1380003 Napa 641-1106) and I was going to press these on. My questions are: Is it acceptable to leave the drum where I do not have to remove the bearings to pull them off or should I out it the way it should be? If I leave it is it ok that the drum holes are a bit loose on the studs? The drum holes are .517 and the stud shaft is .4375 (7/16). Thanks.
Are the drums aluminum? For several years (‘68 and ‘69 for sure) big block cars got aluminum drums and had bigger studs in their hubs. I don’t know if the mismatch is a problem, but that may explain it. Patrick
I.have replacement drums but these.hubs came from a v8 board member. The studs in it have the taper for the disc brake. I checked the stud size for that in our books at Napa. I actually took some old hubs off of some cast iron skylark drums and they fit fine. This started as a favor for a friend and has been a major pain.
