Drum to disc..rim backspace?

[busboy]

Do 14" steel rims on a 9" drum brake setup use the same backspace as rims used on the KH brake setup? Both are SBP for a 72' Dart, thanks.

 

[67Dart273]

If you use the same axles, and if the rotors are on the outside of the axles, then the backspace will change by the difference of the original thickness of the drums, and the new thickness of the rotors. In some cases this might not be very much

 

[busboy]

Sorry, not sure I understand what you mean :-s

 

[67Dart273]

I'm not sure how else to explain it. The total axle width is determined by "where" the ends of the axle flanges are, PLUS the thickness of the brake drum, which usually ain't much, maybe 1/8" on each side.

So if you convert to discs, using an aftermarket kit, and say, the new rotors go over the outside of the axles just like the drums did, then the axle will be wider by the amount of the thickness of the flange on the rotors -rotors act as a spacer.. Some rotors are quite thick and some are not, so this will "depend."