[Green_WEDGE]

I am going big bolt pattern on my 70 duster and I need some advice on the rear diff. It is an A body 8 3/4 and really dont want to cut the housing to put in 30/13.5 tires with 10in rim. Or should I just cut it because there arent many wheels with that big of an 6-7in offset? I know of Weld and may be Centerline but I dont know any others? o----o<>

 

[fourspeed]

It would look nice, and give you more wheel choices, if you shorten the housing. Given the price of A-body 8-3/4 rears, I think you should sell the A-body rearend, and buy a C or B body rearend to shorten. You'll probably be money ahead - plus it'll have big brakes.

 

[Jim_Lusk]

We run 15x10 wheels on Alan's Barracuda when racing. The springs have NOT been moved. We have about 4" backspacing. We could go a little more but Nascar slicks have a lot of sidewall buldge. Here's a pic of the fit.

[attachment deleted by admin]

 

[70Dustpan]

You won't fit that size under a Duster without them sitting in under the car pretty far. They will hit at the lower parts of the wheel well opening. So I don't think you can get enough back spacing with a stock size housing. Like said before I would have another housing made-up and sell or hold on to the stock A body 8 3/4.

 

[Green_WEDGE]

I know I have to cut the wheel well and move it forward for the 30in tall tires. But cutting the diff or any othere diff means the use of green bearings,that dont like long road trips and what is the going price to have that dun? what should I have it cut it to? I am moving the spring in, the inner wheel wells and using some tires I barowed to try to make them fit. What size of off set should I go with?

 

[70Dustpan]

You don't really need to move it forward just cut the lower part of the opening. For 10's I think 3.5 and 5 are the most common B.S. The best way to find you rear-end size is to get you wheels and tires, put them under the cars a measure from wheel back to wheel back. Why can't you still use tapered bearings after have them cut down?

 

[Bigcube]

Are you going to move the springs in? If so then cut a rear to fit. It's not so bad on a duster, but on a Dart, the shorter the BS of the wheel the easier it is to get on/off the car. Remember the wheel has to go out and over the brake drum to come off the car. I ran a 15x10 wheel with a 3-?/? back space and a 10.5x30 M/T ET Street tire. I had about 2" added to the wheel opening in the front. With a deep BS my tire would hit the 1/4 long before it was over the drum brakes.

This was my car in it's childhood BBD

EDIT> I added the BS of my old wheels

 

[abodyjoe]

i can't help on what size you you should cut it to but definatley don't cut the A-Body housing... like stated above find a B or C body housing and cut that down. the a-body housing will bring you a few $$$.

 

[Jim_Lusk]

If you're moving the springs you won't have any trouble fitting the 15x10s in there. The slicks on the back of Alan's car are Nascar 27". Obviously the wheelwells have been cut, but the car has been lowered quite a bit.

 

[Bakaruda]

Befor we cut my car I put 295-50/15's. It was tight but looked good.

 

[Green_WEDGE]

Hay Big cube could you tell me the length of your rear diff. From drum to drum? Thanks

 

[Bigcube]

The best way to make sure things fit is to get the wheels and tires you plan on running, then cut the rear to fit. It's the only way things will fit perfect. I don't recall the exact width when I had the stock frame but I think it was around 48-49" drum to drum. The pic I posted was from 2001, right after that pic was taken, I tore the car apart and had a full chassis built.

 

[Midnight Special]

Are you going to move the springs in? If so then cut a rear to fit.  It's not so bad on a duster, but on a Dart, the shorter the BS of the wheel the easier it is to get on/off the car.  Remember the wheel has to go out and over the brake drum to come off the car. I ran a 15x10 wheel with a 3-?/? back space and a 10.5x30 M/T ET Street tire.  I had about 2" added to the wheel opening in the front.  With a deep BS my tire would hit the 1/4 long before it was over the drum brakes.

This was my car in it's childhood   BBD

EDIT> I added the BS of my old wheels 

Jim, could you explain how ya had 2 " added to the wheel opening and maintain such a nice radius . Wish i would know how

 

[BBLM23]

http://www.bigblockdart.com/techpages/wopen.shtml

 

[Bakaruda]

Check out 325/45-17 from M&H.

 

[b569rr]

I have a standard A body width Dana and 28" x 13.5" tires and a 7.25" backspace. I'm pretty sure that 30's won't mount to MY car but it's a Dart. To get the tires off of the '67, the suspension must hang from the car and I have disks. My backspace and details are in the tire / wheel section. I did it for a sleeper look from the side.

 

[400duster]

Midnight Special, I just met your son the other day. I had my duster on the trailer and he stopped me. I am looking for some parts, (manual steering box) and would love to have a look at your rides. Drop me a line.