narrowing a b-body rear

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Louie70Dart

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Ok, I had the wrong link. I now have the link I was referring to.


I have a housing for a b-body. Along the way I picked up the pieces to end up with a whole 8 3/4 rear, backing plates shock mounts, everything but new perches. I would like to get this narrowed to use in my '70 Dart. I have the chink, the pig clutch SG, b body axles, all.
I looked thru the search and I ran across this list from a link, and it's also listed farther in the link. My question is how accurate are these numbers? Thanks!!

http://www.moparts.org/Tech/Archive/axle/16.html
 
What year rear? It can be made to work the way it is with proper wheel backspacing.

Is this just a street car?
 
That chart is wrong. A-body 8 3/4's are 52 5/8" flange to flange. Perch centers are 43". According to Dr Diff, you can narrow the housing down to a minimum of 51 1/4" using his 1/2 offset hanger kit. Any shorter then that, and the outer U-bolts will be into the housing ends.

EDIT: I see you changed the link...
 
LOL, sorry about the bad link. I just went and measured the housing, flange to flange and it's 54 1/4. According to the moparts list, if it's right, that makes it a 65-67 housing. The reason I would like it narrowed is because I, or anyone if I should end up selling it, would have a greater option of wheels. I hope anyway. I think I will need new axles because the ones I have, the splines are back cut. It narrows/thins down right after the splines, which means I cant shorten them down, right?
 
It's your money, but is it really worth the inch off of each side? I guess factory wheels could be an issue, but anything aftermarket with an inch to an inch and a half deeper backspace is gonna work nicely I would think.

I run a 68-70 B rear in my Sport, which is wider yet, and 5 1/2" BS wheels and they fit perfect. Although my wheel wells might be a tad wider.
 
What a waste of time/effort/AND MONEY!!! :banghead:

Cut the Perches off...weld them BACK on = A-Body Frame Width Specs...with the correct pinion angle.....and install that B-Rear in that A !!! Then Enjoy!
 
LOL, yeah, that's what I have heard from many others. Although some said why even relocate the perches? the mounting is what, one inch total? That comes out to 1/2 inch each side? That would definitely be the least expensive route, as the perches are still there. I have some cop wheels, how much room would I have? Do I measure the backspacing from the 14 inch OEM wheels and compare to the 15 inch wheels? Then the other measurements? MY GOD!!! So many questions! Thanks to all.
 
Prine said:
What a waste of time/effort/AND MONEY!!! :banghead:

Cut the Perches off...weld them BACK on = A-Body Frame Width Specs...with the correct pinion angle.....and install that B-Rear in that A !!! Then Enjoy!
Click to expand...

Absolutely this.

With a 65-67 B rear I would just move the perches. While I was at it I would move them to 42" C-C and use one of Dr. Diff's 1/2 offset kits. With the offset kit you can run a 9" rim and 275's for tires.

As far as wheel options, you'll have plenty. In fact, you'll probably have even MORE options, especially with 17 and 18" rims, since most of the newer wheels have more backspacing. Even with 15" aftermarket rims you won't have any problems. The only place you may have to do a little work is stock wheels, but even then there should be some available with what you need.

Stock 70-74 Darts are pretty close to needing zero offset wheels, ie, 8" wide rims with 4.5" backspace, 9" wide rims with 5" backspace. The 65-67 rear would only move that about 3/4" per side. With a 1/2 offset spring offset, that would mean that a 9" wide rim with 6" backspace would be perfect. And there are plenty of options in that size.

Plus, if the axles taper after the splines it means they can't be shortened. Most B body axles can't be cut down and resplined because of that taper. C body and truck axles are the best candidates for that.
 
Louie70Dart said:
LOL, yeah, that's what I have heard from many others. Although some said why even relocate the perches? the mounting is what, one inch total? That comes out to 1/2 inch each side?
Click to expand...


The only issue there, is it can cause premature wear on the spring eye bushings. Because one end will have downward pressure and the other end upward pressure from the spring being canted.

You can get replicated OEM wheels with different BS also, I think Specialty Wheels sells them.
 
Thanks everyone! I think that is what I will do. Leave the width as is and relocate the perches, and look into the Dr. Diff offset kit. I will get new green bearings tho. No sense it being what I think is stupid cheap. Thanks again!!
 
Louie70Dart said:
Ok, I had the wrong link. I now have the link I was referring to.


I have a housing for a b-body. Along the way I picked up the pieces to end up with a whole 8 3/4 rear, backing plates shock mounts, everything but new perches. I would like to get this narrowed to use in my '70 Dart. I have the chink, the pig clutch SG, b body axles, all.
I looked thru the search and I ran across this list from a link, and it's also listed farther in the link. My question is how accurate are these numbers? Thanks!!

http://www.moparts.org/Tech/Archive/axle/16.html
Click to expand...

that list has the correct measurements..
 
Louie70Dart said:
Thanks everyone! I think that is what I will do. Leave the width as is and relocate the perches, and look into the Dr. Diff offset kit. I will get new green bearings tho. No sense it being what I think is stupid cheap. Thanks again!!
Click to expand...

Personally, I would stay away from the green bearings. Yes, they work. But the stock tapered bearings are a superior design, and adjusting them isn't nearly as hard as some people make it out to be.
 
72bluNblu said:
Personally, I would stay away from the green bearings. Yes, they work. But the stock tapered bearings are a superior design, and adjusting them isn't nearly as hard as some people make it out to be.
Click to expand...

X's 2.

Chances are the bearings you have are still good, clean and inspect them, if they move smoothly and don't appear to be loose, get a needle for your grease gun and fill em up.
 
72bluNblu said:
Personally, I would stay away from the green bearings. Yes, they work. But the stock tapered bearings are a superior design, and adjusting them isn't nearly as hard as some people make it out to be.
Click to expand...


Bad Sport had a good statement about green bearings also. The shop I talked to about narrowing the housing mentioned green bearings also and then something about adjusting the axles to make sure they are centered or something? I'm not sure if it was no adjusting/aligning with them? If that is the case, aligning/adjusting the axles, how tough is that to do right the first time? The guy said it may take up to three times to get it right? I think I need to do some looking so I can come\back with a better understanding of what's going on. I don't want to hear the BS from some of the more advanced members here about what they THINK I need to do before asking questions. I'm afraid I would not be very nice in my response to any comments I take to be smart *** and unhelpful. I will try to be cool and calm, but I can't promise. LOL. But I am VERY appreciative of what help I have gotten so far! Thanks to all of you!
 
72bluNblu said:
Personally, I would stay away from the green bearings. Yes, they work. But the stock tapered bearings are a superior design, and adjusting them isn't nearly as hard as some people make it out to be.
Click to expand...

x2

"Green" Sealed Axle Bearings are for Drag Racing...no side/side loads.
 
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