8.75 in early a body clearance issue

[Slantsix64]

i have a 1966 dodge dart i bought and it has a 8 and 3/4 rearend big bolt pattern in it. the problem is i believe it was not cut at all. due to that the passenger side tire cannot be wider than 195 r70 r14, but the other side has a decent size. my question is can i buy a rim with different back spacing size for better clearance on that on side?Thanks in advance mopar nuts!

 

[4mulas]

i have a 1966 dodge dart i bought and it has a 8 and 3/4 rearend big bolt pattern in it. the problem is i believe it was not cut at all. due to that the passenger side tire cannot be wider than 195 r70 r14, but the other side has a decent size. my question is can i buy a rim with different back spacing size for better clearance on that on side?Thanks in advance mopar nuts!

When you say you can not fit wider than a 195 70 is the problem of clearance on the outside or inside of the tire wall?

This sounds unusual. First measure from flange to flange (right behind where the backing plate bolts onto) It should be 52 5/8" if it's a proper a body diff or one narrowed to A body dimensions. And report back

 

[72bluNblu]

Sounds like the perches aren't centered. It's not unusual for them to be off by as much as a 1/4" to one side or the other from the factory. Much more than that and you've got issues. And it sounds like yours might be shifted more than that.

In addition to measuring the width of the axle to make sure it's actually A-body width, you can measure from the flange to the perches on each side. Obviously that measurement should be the same side to side. If it's not the axle won't be centered.

 

[Slantsix64]

thanks for the reply the issue is on the driver side inside of the tire wall. i know its not an abody rear end it has to be a b body its already mounted in the dart. is there any way i can run a steelie rim with a different backing size so that i can use a wider tire on one side to make it look some what even? ill take some pics and post them soon

 

[Slantsix64]

the previous owner just bought a 8 and 34 rebuilt it and stuck it in not even knowing there's different lengths etc. just trying to see i can get a rim that has the center stick out a little more , so the rims outer lip can go more in so i can run the same size tire on both sides

 

[4mulas]

the previous owner just bought a 8 and 34 rebuilt it and stuck it in not even knowing there's different lengths etc. just trying to see i can get a rim that has the center stick out a little more , so the rims outer lip can go more in so i can run the same size tire on both sides

I think what you're trying to do is completely wrong and I would not recommend it.
If money is an issue buy a used 7 1/4" diff and slap that in. They are cheap and plentiful.
Otherwise buy and 8 3/4 a body housing and axles, change the center section over or have the b body diff shortened properly' get the right axles and be done with it.
Good luck

 

[SGBARRACUDA]

I think 72bluNblu put you on the right track in post #3. Anything worth putting time and money in, is worth doing the right way. And it's the safe way.

 

[Lelo Dart]

https://www.summitracing.com/parts/...ReAIiNHAKjznIZKv1A9MvrCslu2RNYa1dyxoChqrw_wcB
Use these, can be found cheaper, and have them welded in at 43" apart to center your rear end.

 

[72bluNblu]

https://www.summitracing.com/parts/...ReAIiNHAKjznIZKv1A9MvrCslu2RNYa1dyxoChqrw_wcB
Use these, can be found cheaper, and have them welded in at 43" apart to center your rear end.

Dr. Diff sells them for $15, and while I do a lot of business with Summit I try to send Cass my money whenever I can. He has awesome stuff and he knows what he's talking about. After he puts them in a flat rate USPS box it will still save you a few bucks.
Leaf Spring Perches (Pair) for Mopar, Ford, Chevy/GM

As far as the 8 3/4 goes, boy, that would have been good information to have to start. If you don't have an A-body rear end you're going to need rims with more backspacing, every other factory 8 3/4 is wider and not by a little bit. Even the narrowest B body rear axle it could be is more than 2" wider, which means an extra inch of backspacing on each side if it was centered properly. If you want to keep steel 14" rims then they'll probably have to be custom made, there aren't a lot of options that have that much more backspacing than the stock wheels. Especially if you want them to match. But, since I don't know what the width of your rear axle is, or how off-center it is, I can't even begin to suggest what kind of backspacing you would need. There are 4 different B body rear axle widths with standard axles, and two more if you want to consider the ones with tapered axles (which you probably don't have). I would bet it's either a 65-67 or a 68-70 since I don't think anything else would even fit into the wheel wells of an early A, but there's still a 5/8" difference in width between those two.

And regardless of which 8 3/4 axle you have under there, it needs to be centered. If it's not, you need to fix that FIRST and work from there. If it's as off center as you suggest then you could be causing problems with your driveshaft angle and u-joints. Not to mention your car won't handle the same way turning right vs turning left. And if this is the previous owners version of a good job, you need to check everything. Just throwing one one wheel that has more backspacing on it won't fix all the problems the axle not being centered will cause.

 

[Slantsix64]

thanks for the info! yes i think im going to just pull it out and find me a 8 and 1/4 from an a body would that be a direct bolt in?

 

[Lelo Dart]

Well... not direct. You should try to get the driveshaft from the donor car. I don't know about early A's but I bet your driveshaft will be too short going from a 8 3/4 to a 8 1/4 and you my need to get the donor shaft shortened. There is always some adjustments that will have to be made changing rear ends. If you could find a 8 3/4 A body that would bolt in, would be going back to small bolt pattern wheels, there's always something.

 

[72bluNblu]

Before you get too crazy I think you should measure the 8 3/4 you have to confirm what it is, and measure the backing plate to perch distance to see how far off center it is. Then you can go from there. Because switching to an 8.25" rear will require a longer driveshaft, and an A-body 8 3/4 will be SBP and need new BBP axles and brakes. You have an 8 3/4 already, it would probably be cheaper to have it shortened and buy new axles. A-body 8 3/4's are really expensive and you'd still need new axles. The 8.25" wouldn't be as expensive and the new driveshaft would be cheaper than shortening a housing and buying new axles, but you'd have to find one and they aren't as easy to find as they used to be.