Is the 73-up the same width as the 72-down?
Many thanks.
Many thanks.
A body 7.25
- Thread starter moparmarks
- Start date
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Professor Fate
Push the button, Max...
If it's the big bolt pattern '73 and up, it'll be just a touch wider overall because of the greater axle flange offset needed to run the BBP brakes.
If it's a small bolt pattern '73 and up, it should be identical width to the '72 and earlier rear.
Both will have the same perch spacing.
If it's a small bolt pattern '73 and up, it should be identical width to the '72 and earlier rear.
Both will have the same perch spacing.
Is the backing plates on the big bolt 7 1/4 the same as the 8 3/4 ?
Professor Fate
Push the button, Max...
If you mean will they fit an 8 3/4 with aftermarket BBP axles, then yes (no with stock sbp axles)- they should have the correct offset and I believe they should fit the 8 3/4. BUT- they may only be drilled with four holes and need the fifth hole drilled. I honestly don't remember if my (10x2 1/2" brakes) BBP 7 1/4 had four or five studs holding the backing plates to the housing flange. I know the early ones only had 4.
Actually, I believe the LBP housing is narrower, You can't just swap LBP axles & backing plates into a SBP housing. I have both, I may take time to check that tomorrow.
I thought all the 7.25 housings had 4 bolt flanges. Is that not correct? I know my 64 only has four.
Professor Fate
Push the button, Max...
There's also bearing and axle dia. differences that preclude swapping axles, but I believe the housing width is the same.
I just pulled a few rearends apart that I have here. Large bolt pattern 7.25 has the same backing plates as an 8.75. Both 10" brakes ,both have the 5 bolt mounting. Side by side they look and measure the same.
Also ,the 7.25 had sealed axle bearings, no adjustment. I don't know if all 7.25s have the same. Never messed with one before.
Also ,the 7.25 had sealed axle bearings, no adjustment. I don't know if all 7.25s have the same. Never messed with one before.
I have a 7.25 large bolt pattern rear. It measures 51 1/2" from the housing end to end, over the cover.hope that helps.
My 75 7 1/4 has 5 bolt flanges
The housing is narrower, RRA's spec is about right, 72blunblu's sticky has them listed right at the top.
As does My LBP 7.25" out of a '76 4dr. Dart. They share the same 10" backing plate w/the 8.25".
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