Bbody 8 3/4 question

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zigs

zigs

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I'd like to get some direction here.
I have a bbody 8 3/4 from a Belvedere
. I have searched but can't find an article from someone on here that used a "B" on an a body without cutting the axle housing using 16 or 17" wheels. This is for a 70 Duster .
Anyone know this article
 
Mine is a b body rear. You will just need to measure for proper backspacing. I run a 26x 10 r15 slick. Rims are 10 inch wide. 7.5 backspace.
IMG_20190706_171137_651.jpg
 
Unless it is from a 71-71 B body, that is a winner. You just need to remove the spring perches and move them in toward the center 1/2" each.
 
Back in the late 80’s early 90’s I ran the same rear and in my Demon. With the springs bowed out that little bit (I never noticed any difference) the car was fine. I only ran 15” cragar SS with a 28” tall tire. No idea about offset or back spacing then. I just bolted on the 15”x8” rims and started to drive. My only real issue was a year or two later I had to replace shackle bushings because they wore in evenly. I did not have the equipment then to move the perches out properly.
 
I just done it, I've done it in the past, and I'm about to do it again. This is my most recent one..... I made a video. In this video, I replaced the 8.25. Replacing a 7.25 rear end, you'll need backing plates (alot of 8.75 rear ends come with backing plates), U-bolts, and a shorter drive shaft. You can re-drill your shock mounts, or get 8.25/8.75 shock mounts. '65-67 are the best years because they are a little more narrower than the '68-70's.
 
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All good info , this is what I wanted to hear. I have everything coming that I need to make the switch. Diff is being rebuilt. I appreciate the help.
Now anyone have a 70 , 340 cheap
LOL.
 
This is an easy swap.
I did it for my '74 Dart Sport and it was simple.
You just have to move the spring perches toward the center 1/2'' on each side making them 1'' different than the B-Body factory mounting spot.
You can get new spring perches from Dr. Diff for like 15 bucks, so that part is cheap.
BTW, the Dart Sport and Duster have the same room in the back, they are built on the same platform '70 to '76.
The great part of this swap is that you automatically get the big bolt pattern axles, and the housings are a lot cheaper than the A-Body ones, plus you don't have to buy axles.
I used a '69 housing in mine so it is slightly wider than the '66-67 you have.
I run 255-60-15 tires on a 15 X 61/2'' factory rallye wheel and have enough clearance that i could easily run a 275 width tire with the right offset.
As it is, I have about an inch and a half clearance between the inside sidewall and the spring, and about an inch to the wheel lip which i rolled up to be safe.
I also used 002 and 003 Super Stock springs on my car, but that doesn't really matter here, unless your springs are sagged badly like mine were, that's one of the reasons that i rolled the wheel lips in initially.
I have some detailed pics in my build thread if you would like, but it looks like 318 willrun has it covered for the most part in his video in post #6 other than cutting off the perches and welding new ones on, which is what i would do especially if you have new bushings in your springs..........
The link is at the bottom of this post to my build thread if you are interested.
 
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