will the 2 1\8 inch long bolts from langs be long enough to mount my floating hubs? i made them with countersunk holes and a 1\4 inch flange. philip
If you mean the 6 bolts that hold the hub in the wheel, they are not suitable for mounting a floating hub, no matter what their length. It's fine to put them through the hub flange, but do not expect them alone to support the weight of the car and to keep the floating hub bearing on location. They will move in the clearance they have with the wheel hub and will allow the bearing to move and the nuts to work loose. Have also seen those actually break in that application.
I suggest you counterbore the brake drum slightly, (maybe .050), to closely fit the O.D. of your flange and also rivet the flange to the drum, (flush riveted on the drum side), in the 6 places between the 6 bolts. You're now depending on the brake drum to locate on the boss at the back of the wheel hub and keep your bearing on location. Others have drilled & tapped through the floating hub flange, & brake drum, into the wheel hub flange, then installing 6 button head cap screws with Loctite, to secure the bearing.
Maybe you're taking all of this into account already, since you're only really asking about the bolt length, but I thought I'd mention it, just in case.
yes i plan to put in the other six flat heads
i am not planning on using any rivets. do you think the six 3\8 hub bolts and six 5\16 additional bolts tapped into the hub will be enough? philip
It probably will be enough. I wouldn't consider that the 3/8 hub bolts will contribute much past adding to the clamping force of the assembly. All of the locational & shock loads will be taken up by the 5/16 bolts. Maybe up them to 3/8?
i may do that the ones you buy are 1\4 but there is room for 3\8