8 3/4 swap

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Bob's Dart

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Need some help. Did a 66, or 67 Plymouth Valiant come with a 8 3/4 rearend. If so would that bolt up to a 67 Dart, or a 72 Demon. Thanks for the help.
 
Bob, I don't think the '66 or '67 Valiants were available with the 8-3/4. However, I know the 8-3/4 was available in the '67 Dart. A friend of mine had a '67 Dart GTS that was ordered from the factory with a 383, 727 torqueflite, front disc brakes (non-power), and the 8-3/4 rear end. Not very many of the '67 Darts were so equipped, however. I ran an 8-3/4 rear end and springs from a '70 Dart GT in my '65 Barracuda for 40 years; the whole assembly was unbolted from the Dart at the junkyard and bolted into the Barracuda with no modifications. I'm not sure about the '72 Demon; the width might be different.
 
Bob, I don't think the '66 or '67 Valiants were available with the 8-3/4. However, I know the 8-3/4 was available in the '67 Dart. A friend of mine had a '67 Dart GTS that was ordered from the factory with a 383, 727 torqueflite, front disc brakes (non-power), and the 8-3/4 rear end. Not very many of the '67 Darts were so equipped, however. I ran an 8-3/4 rear end and springs from a '70 Dart GT in my '65 Barracuda for 40 years; the whole assembly was unbolted from the Dart at the junkyard and bolted into the Barracuda with no modifications. I'm not sure about the '72 Demon; the width might be different.
 
Thank you for the information. The 8 3/4 A body rearends are getting harder to find.
 
There is one difference in a 1970 and later 8 3/4" versus the pre-70 unit! In 1970 the distribution block and vent was moved from the bottoms edge of where the hump starts to a little further down the drivers side axle tube! This results in needing to order the correct set of lines, and may also necessitate getting a longer rubber hose, depending on which car it's coming out of or going into!! Other than that, same same!!
 
I have read from 66 to 72 sould be the same. Just wanted to be sure. I appricate all the help. Was only looking at the Plymouth Valiant as a option. Thanks again.
 
I have read from 66 to 72 sould be the same. Just wanted to be sure. I appricate all the help. Was only looking at the Plymouth Valiant as a option. Thanks again.

They are the same, except for this one difference!! Easily overcome!!
 
There is one difference in a 1970 and later 8 3/4" versus the pre-70 unit! In 1970 the distribution block and vent was moved from the bottoms edge of where the hump starts to a little further down the drivers side axle tube! This results in needing to order the correct set of lines, and may also necessitate getting a longer rubber hose, depending on which car it's coming out of or going into!! Other than that, same same!!
 
Thanks again, for the information, and pointing me in the right direction. AWESOME.
 
All A bodies use the same width rearend!!

That's not actually true.

All of the A-body 8 3/4's are the same width (52 5/8" flange to flange). But the BBP 7.25 and 8.25" rear ends are actually narrower than the SBP 8 3/4 rear ends (51.5" flange to flange). And the SBP 7.25" rears are a different width than the BBP 7.25/8.25" rear axles.

Also, if you're looking for a Duster, Demon, or Dart sport you can use a 65-67 or 68-70 B body rear axle if you move the spring perches to the A-body dimension of 43" c-c. The sport body is wider in the rear, so, you can use a wider rear axle. You do have to watch the backspacing on your wheels though, depending on what size you've got on there now.

Here's a link to the sticky on 8 3/4" widths, the list includes some of the 7.25/8.25" dimensions as well.

An accurate 8 3/4" rear axle width list
 
That's not actually true.

All of the A-body 8 3/4's are the same width (52 5/8" flange to flange). But the BBP 7.25 and 8.25" rear ends are actually narrower than the SBP 8 3/4 rear ends (51.5" flange to flange). And the SBP 7.25" rears are a different width than the BBP 7.25/8.25" rear axles.

Also, if you're looking for a Duster, Demon, or Dart sport you can use a 65-67 or 68-70 B body rear axle if you move the spring perches to the A-body dimension of 43" c-c. The sport body is wider in the rear, so, you can use a wider rear axle. You do have to watch the backspacing on your wheels though, depending on what size you've got on there now.

Here's a link to the sticky on 8 3/4" widths, the list includes some of the 7.25/8.25" dimensions as well.

An accurate 8 3/4" rear axle width list
 
Thanks again, for all the knowledge, and feedback. Just dont want to hunt something down, buy it, and not have it work.
 
That's not actually true.

All of the A-body 8 3/4's are the same width (52 5/8" flange to flange). But the BBP 7.25 and 8.25" rear ends are actually narrower than the SBP 8 3/4 rear ends (51.5" flange to flange). And the SBP 7.25" rears are a different width than the BBP 7.25/8.25" rear axles.

Also, if you're looking for a Duster, Demon, or Dart sport you can use a 65-67 or 68-70 B body rear axle if you move the spring perches to the A-body dimension of 43" c-c. The sport body is wider in the rear, so, you can use a wider rear axle. You do have to watch the backspacing on your wheels though, depending on what size you've got on there now.

Here's a link to the sticky on 8 3/4" widths, the list includes some of the 7.25/8.25" dimensions as well.

An accurate 8 3/4" rear axle width list

Well, since the title of the thread was 8 3/4" swap, I was speaking strictly to the 8 3/4" rear! Nowhere in his text did he say he was considering a BBP 8 1/4" or 7 1/4", but you are correct!! Still a bolt in tho!!
 
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