The easiest brake upgrade 8 3/4

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n8ling

n8ling

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So I've got a 8 3/4 orig to the car 10 x 1 3/4, Have stock sbp axles drilled to lbp green bearings. (I did notice things are a little snug going together, and yes adj pin removed).
My prob is my drums are toast. Really bad! And would need drilled to lbp.
From what I've been reading here..... If I get 73 < backing plates drums lbp axles etc
Will that work. Bolt in and go??????
 
only bolt and got kits i know of under $1000 is the wilwood kits. i have the 12" rear disc set up on my car. rear disks are over kill but i like this kit because its super lite. 35 lbs for entire brake package. rotors/brackets/ calipers.

 
n8ling said:
So I've got a 8 3/4 orig to the car 10 x 1 3/4, Have stock sbp axles drilled to lbp green bearings. (I did notice things are a little snug going together, and yes adj pin removed).
My prob is my drums are toast. Really bad! And would need drilled to lbp.
From what I've been reading here..... If I get 73 < backing plates drums lbp axles etc
Will that work. Bolt in and go??????
Click to expand...

No, it wont work. MOPAR did not make a large bolt pattern 8-3/4 for the A body.
Either find new or good used 10 x 1-3/4 drums for the small bolt pattern 8-3/4 and have them drilled to large bolt pattern OR replace the original axles with large bolt pattern axles and complete brake assemblies.
New A body axles with bearings around $300 plus shipping. Used...good luck.
Large bolt pattern 10x2-1/2 complete used rear brake assemblies from any 65 up $100 =/- a few bucks.
If your going with new axles I reccomend contacting DoctorDiff. I bought a set from him last year. Excellent vendor, very knowledgable.
 
The SBP axles had a different offset than the BBP axles. The backing plates have an offset to match the axle offset. So if you use SBP axles (even redrilled) you have to use SBP backing plates. You will have to find a set of SBP drums and redrill them to BBP and use them with the correct offset SBP backing plate. If you DON'T, the back of the drums will drag on the backing plates.

IF you use aftermarket or cut down B/C/E axles, they have the correct offset to use the BBP backing plates from other models (including the 73 BBP backing plates).

It's confusing, but just remember to match the backing plates with the axles you are using.
 
I do have a pair of after market axles I picked up some where along the line lbp a body.
So (just can't crack this nut yet!) can I use b/plates from say, 8 1/4 + drums, shoes etc......
That would be 10x2 1/2 ...... Right???? And would work???
 
As long as the axle offset is set up for the non A body brakes your good.
Any 1965 and up large bolt pattern brake assemblies will work. 7.25, 8.25, 8.75, 9, dana

I have a set of 11x2-1/2 off a 74 B body 8.25 on my 72 Demon's 8.75. I've put 10x2-1/2 from an Aspen/Volare 7.25 on an 8.75. If the backing plate is missing the 5th stud hole just drill it yourself.
 
This offset thing is killin me. So 65+ non a body anything. What is the diff?
 
disc brakes off of new jeep's with 8.25 rears

when you got LBP axles did you get A (2") or B body (2.5") offset?
 
Here is a photo 8 3/4 A Body housing. I used 10x2 1/2 drums and backing plates from a 72 B Body. The axles are Yukon and have the B Body drum hub register(axle center) that is larger than the A.Take the Aftermarket axle you have and your A body drum and check to see if it fits over the drum register. If the "drum" hub is too small then you have the correct aftermarket axle to use the B Body brake parts.
I hope this helps only because the aftermarket axles were available with both sizes of drum registers.This will also determine the backing plate offset.I've had both but now I think the aftermarket has discontinued the A body style drum hub register.
 

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I did my best to un-complacate the text. Sometimes what you think is hard to put into words.
 
Next question. Wheel cylinder the same??? Abody 10x1 3/4 to bbody 10x2 1/2 b/plates???.... Should be same right?? checked axles set up for b body and backing plates from 68-70 b body 8 3/4. So.......drums and shoes and h/ware kit..... Good to go right???
 
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