Narrowing the rear end

[chevy72blu]

I am running a 14.5" wide tire in the rear on a 10" wheel (dont have the BS #'s with me, but im sure I can find them), and a GM 8 7/8" 12 bolt. The rear is out of a 73-87 3/4ton (I believe). I have already gone through it with gears/LSD.

My current set up works fine- but my tires stick out about an inch and a half, maybe 2" from the lip of the fender.


What all is involved in narrowing the rear? Doesn't seem like it would be too hard to pull the drums, remove my axles, throw the thing on a long steel band saw (my dad's company has one),make a jig to hold it level, section out 1.5-2" on each side, re-weld, and gusset it. I would make the cuts based on available upgraded axle lengths, and then put the thing back together. Of course I would have to get it 100% strait before re-welding it- I imagine this is where the danger is. If I can, I'd like to not have to mess with my fender wells, and I think I have enough room to do it. If not, Ill buy some aftermarket steel tubs and weld them in, mine are pretty dented up anyway.

I have to pull the rear out anyway when I start making my trailing arm setup.

Where is the best place to make the cuts? Inside, middle or outside?

Thanks for the help guys!

[collin86]

if you are only sticking out 2 inches or so on either side i would not mess with narrowing it and just get different backspace wheels (2" more on each side)

if you are set on narrowing you are on the right track. you just need to get it in a jig to make sure everything is perfect and straight. as far as axels go you can call stange or moser or yukon and tell them your spline count and the length you need and they will make them for you. so you can narrow as much as you want.

[whatnow123]

Have you checked the difference in width on for the 67-70 rear ends? That might put you in the ball park. I know they are about 1.5 inches narrower than the 71/72 and it might even be more on the later rear ends. That way you woudn't have to narrow anything, all your "inner'ds" will swap right over and it would already be set up for trailing arms.

[chevy72blu]

Originally Posted by whatnow123

Have you checked the difference in width on for the 67-70 rear ends? That might put you in the ball park. I know they are about 1.5 inches narrower than the 71/72 and it might even be more on the later rear ends. That way you woudn't have to narrow anything, all your "inner'ds" will swap right over and it would already be set up for trailing arms.

Thats a good idea, and would keep me from having to buy a few parts. Ill take some measurements and look into how much I could get out of the back spacing, sounds like thats what I should check out first. My dad bought the wheels/slicks for me for my birthday a few years back, and im sure he just went with a safe BS.

Im wondering if I should wait to see how well I can hook the thing up my new suspension before I do this anyway. If im still spinning, I know ill need to mini-tub and go to a bigger tire.

Thanks for the help!

[69trk]

I'm running a 14.5 qtp with a 4.75in. bs. on some centerline wheels that are only 9.5" wide. They don't stick out at all. I wish my rims were 12in. wide but i can't find anybody that make them in 16". I did have to widden the wheel tubs, i just went to salvage yard and found some and spliced 2" into mine. If i can find some 16x12's i'm going to go ahead and get 5" of backspacing.