1968 rearend swap

[68 special]

I need some help to determine which is the best route to go.
Right now I have a '67 3.00 rearend. The whole drive train was swapped in the 70's. I want to install a posi or trac-loc.

Not sure if I can rebuild mine into a posi or is a complete swap in order?
Should I go with a 9" or stay with the 8"?
I read that the early 90's Explorers,(1/2" wider), will work,but have to relocated the spring perches and the offset to the drive line might be a factor, (2", R).

also, heard the Versailles (3/4" narrower), are a direct bolt in????

Let me hear your thoughts.

Thanks,
Bret

 

[CougarCJ]

8 inch rear ends are plenty strong. No drive shaft change if you stay 8 inch.
9 inch rear housings can be sourced from any 1969-70 Cougar, or 1969-70 Mustang with 351 cubic inches or bigger engine. All Mustang and Cougars from 1967-70 use the same rears dimensionally. Perches, axles, and over all width is the same.
Pretty sure that Ford Explorer rear ends are 8.8's.
Versailles's are not good choices any more, for 9 inch with disc brakes.

One of the best ways to go rear disc is to use Crown Victoria, (Explorer too?) rear disc parts with adapters for your current 8 inch or next 9 inch.

For simplicity, stay with your 8 inch and purchase a TruTrac third member. Choose your ring and pinion gears wisely.

 

[dalorzo_f]

+1 on the 8" and Trutrac. Unless you are building mega-Hp and planning to flog it that will hold up a long time.

As for rear discs, no real value other than bragging rights, for the most part.

If you are determined to go 9 inch, I believe they on some 67-71 Fairlanes, Comets... and I think Torinos and Motntegos in the 59.25" size on the 68 Mustang.

There is some interesting info on the 9" on this site:

http://kevinstang.com/Ninecase.htm

 

[nikzack]

Stick with the 8 inch and just swap out the carrier. Stick to under a 3.55 I like the 3.25 better on the hwy. There a always a bunch of rebuilt posi 3rd members on ebay for aroung 800 bucks

 

[Mosesatm]

I purchased an 8" open (not Trac-Loc) from these guys.
http://www.justdifferentials.com/product-p/rebf8-custom.htm
and was happy with it.

 

[rvrtrash]

I bought the rear end for my Tiger from them as well. No complaints.

Steve

 

[robert campbell]

Bret,
I would not bother with discs unless you auto cross or road race. Depending on your budget I might consider a slight narrowing of your rear end. You can take two inches out of it and better center your rear tires and run a bigger footprint. But you need to consider the wheel and tire you want to run. I have fronted this for client cars that are Falcons or Comets and have very restrictive wheel wells. We were able to get a much larger tire under a stock wheel well.

8 or 9 inch will be based on how much you like to drop the hammer. Ask Steve, I build my cars to hammer and yup, I hammer them. Even new 8 inchers will handle a lot or hp if you get the "new" cases. I sold a 3.70 open 8 inch to a friend with a 289 4 speed 1967 Fastback with basic street tires. He hammered second right in front of my house, exploded the case and when he got to a stop, we pulled the drive line out with the yoke, front of the case and the pinion gear still attached to it!

That is why the "N" case 9 inch was developed. There are also certain cases that will handle the hp similar to a "N" case. Across the board, the 9 inch stock cases handle a lot more hp than an 8 inch.

Rob

 

[Bumblebee]

Keep the 8" rear and consider a Detroit true trac (not locker). Great strong street diff. I have one in my 66 convertible running a 410hp ROUSH and believe me it's plenty strong and has very nice road manners. I had an Auburn posi before that but it crapped itself....

Good luck with it!

Cheers

 

[rvrtrash]

Bret,

8 or 9 inch will be based on how much you like to drop the hammer. Ask Steve, I build my cars to hammer and yup, I hammer them.

Rob

I remember the front end pointing at first one ditch, and then the other...... oh wait, that was me. I don't think Rob's accelerator pedals have return springs on them, because they always seem to be resting on the floor.

Steve

 

[68 special]

OK, since this is a budget swap, I picked up an Explorer rear, cut all the useless brackets off. Now need to find the replacement spring perches. Thought I had seen something here, but went through 15 pages!!!!

Does anyone self them or do they have to be fabbed?

Thanks,
Bret

 

[robert campbell]

Brett,
See link below. Might want to have your tube diameter and spring width when you call them.

Rob

http://www.ruffstuffspecialties.com/catalog/88PERCH.html

 

[whodat]

Anybody use a Currie Enterprise setup? They are in Mustang Monthly this month.

 

[robert campbell]

I have ordered in two of them. Both 9 inch in custom widths to allow for a bit more tire. One is in my brothers 1967 Fastback and the other is in my other brothers 1964 Comet Caliente.

Both work just great and I had no problems. Currie has been in business for a long time.

If you like bigger tires, you may want to look into a custom width. Does not cost anymore and you will be surprised what a couple inches will do. Make sure you have the wheels you want in hand to ensure all works correct.

If you are staying stock, then just go with the stock width.

Rob

 

[68 special]

Thanks Rob, ordered a pair. they have tabs that can be removed to fit different tubes, so looks like they are a perfect fit.

Now to get the old brackets cut off and cleaned up. Unfortunatley, I don't have a nice big lavish shop, so waiting until the rain isn't running down my back.


Bret