Longgone said:
So for example the Yukon axles would have the proper offset to use with your everyday, over the counter, 74 Duster drum? Does this mean that you must use the wider shoes from an early B or the later model A`s? Do you still have to do anything with the backing plates? Before I spend money on axles I`m trying to find out if I`m opening a can of worms. Sorry for all the questions ,but I want to do it right the first time.
To put it as simply as possible:
No matter what drums you use, 10 x 2", 10 x 2.5", or 11", you must use the corresponding backing plates and parking brake levers for that size of brake.
The narrow 10" x 1 3/4" drums and plates were used on
ALL A-body 8 3/4 rears. They used special small bolt (4") drums and axles, also these axles have a different space from the back of the axle flange to the backing plate than any other 8 3/4 rear. These also used the small 7/16" studs and had special parking brake levers that cleared the axles. These rears were made from 1967 to 1972, but never made in the big 4 1/2" bolt pattern.
Option 1
Other 8 3/4 axles from B & E bodies had 10" x 2 1/2" or 11" x 2 1/2" brakes. These rears used the bigger 4 1/2" bolt pattern and wider brakes, but they have a wider spring pad spacing and the rears are wider also. You can use these rears, but have to use much more backspacing in your wheels to fit within the fenders, you also have to cut the spring perches off and weld on some new ones 1/2" inboard. A soulution, but not a good one.
Option 2 the one on my Dart
You can take the 8 3/4 axle and weld the 7/16" bolt holes closed and have a machine shop redrill them for 1/2" studs in a 4 1/2" bolt pattern. Also have them drill our drums for the bigger pattern. The bad part is that these drums are getting VERY hard to find anymore. Although most people don't drive their a-bodies enough to wear out a set of drums. You can also buy a set of stronger aftermarket axles instead of having yours welded and redrilled.
Option 3
Get a set of new aftermarket axles, or have a set of b-body axles cut shorter and re-splined. Now get a set of wide 10" or 11" drums, backing plates, and parking brake levers, this would be a bolt on option. But the bad thng is, you are going to end up about an inch wider, which on some a-bodies will eat up precious fender clearance. (except Dusters, lucky bastards)
Option 4
Rear disc brakes. This will be custom, and you will need new axles because the a-body axles have a smaller center register than all other 8 3/4 axles. Your best bet would be to call SSB or Wilwood and talk to they so they can help you put together a kit that will fit.
Option 5
Chuck it all out the window and do mini-tubs, relocate the springs, and have a custom narrowed rear built.
