Backin Plates...

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RustyRatRod

I was born on a Monday. Not last Monday.
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Are the backin plates different on A bodies from 10 x 2.5 to 10 x 1 3/4? Speaking of 8 1/4 and 8 3/4. Thank you drive through.
 
There is also a difference in where the brake shoes rub on the backing plates, 1-3/4 and 2-1/2 are NOT interchangeable...
 
Aight den. I either need some 10 x 1 3/4 backin plates for the 8 3/4, OR I need to modify the ones I have for the 7 1/4.
 
I've used 8.25 rear end backing plates on my last two rear end swaps, going from 8.25 to 8.75. Some have used backing plates from the 7.25, but you'll need to drill holes.
 
I've used 8.25 rear end backing plates on my last two rear end swaps, going from 8.25 to 8.75. Some have used backing plates from the 7.25, but you'll need to drill holes.
I used 7.25 complete brake set up off a 74 rear, on my 8.75 converted to BBP, Direct bolt on no modifications.
 
I used 7.25 complete brake set up off a 74 rear, on my 8.75 converted to BBP, Direct bolt on no modifications.
If a guy has a small bolt pattern 7.25, it may be different. I just literally tried it about 2 weeks ago on my '74 Duster. It has SBP, and the holes in the 7.25 backing plates were off, even if I would have drilled the 5th hole. Also, I would have had to drill the drum, or get a drum that would work (seems a '64 Rambler drum is 9 x 2 with 5x4.5 pattern). I'm just using the 10" backing plates.
 
I used 7.25 complete brake set up off a 74 rear, on my 8.75 converted to BBP, Direct bolt on no modifications.
Yes, the large bolt pattern 7 1/4 plates are a bolt on. Mine are small bolt pattern, which only have four holes for the housing ends and not five. I'm just wondering if "everything else" is the same. Either way, I'll get it did.
 
If a guy has a small bolt pattern 7.25, it may be different. I just literally tried it about 2 weeks ago on my '74 Duster. It has SBP, and the holes in the 7.25 backing plates were off, even if I would have drilled the 5th hole. Also, I would have had to drill the drum, or get a drum that would work (seems a '64 Rambler drum is 9 x 2 with 5x4.5 pattern). I'm just using the 10" backing plates.
Yes small bolt pattern will not work, BBP direct bolt on using Dr. diff axles.
 
I've used 8.25 rear end backing plates on my last two rear end swaps, going from 8.25 to 8.75. Some have used backing plates from the 7.25, but you'll need to drill holes.
I did this when I went to bbp axles. I recommend it. Fewer options to worry about.

Or..... liberty discs?
 
I'm staying with small bolt pattern and drums in the rear.
 
7.25 bearing is smaller in diameter than 8.25 or 8.75.

7.25 backing plate center hole is too small
 
7.25 bearing is smaller in diameter than 8.25 or 8.75.

7.25 backing plate center hole is too small
Nope, not by much AT ALL. In fact, I could almost clean the dirt and rust out of the center hole and the 8 3/4 housing end would just about fit. It won't take much with a dremel AT ALL. In fact, I'd bet I could pull it in just by tightening the nuts down. It's THAT close. I damn near pushed it all the way in by hand.
 
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