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Topic: 8.8" rear end questions (Read 5184 times) previous topic - next topic

8.8" rear end questions

After reading tons of threads about 8.8" swaps, I'm still left with some questions.  My first question is why more guys don't swap in SN-95 rear ends, instead of TC rear ends.  By swapping in one from an SN-95, you'd get bigger brakes and a 5 lug pattern out of the deal.  Where as Fox Mustang 8.8's are about 2.5" narrower than T-Bird 8.8's, the ones that were installed in SN-95's are from what I read, only an inch narrower than T-Bird 8.8's. 

What's the story on this?  I'd love to hear from anyone in the know.
William

8.8" rear end questions

Reply #1
I put a Mark VII rear end in mine. It's about an inch wider than the T-bird/Cougar rear. It's five lug disc brakes. And the reason that pushed me over the edge.... I had a Mark VII parts car so it was basically free.
2017 Subaru Outback
2007 Lincoln MKZ
1990 Ford F250 / Banks turbo diesel

8.8" rear end questions

Reply #2
Because of Mark VII rear ends being an inch wider than TC rear ends, doesn't that make it difficult to find rims that will facilitate 245, or 255 width tires?  I thought one of the main reasons why a lot of people swapped in Mustangs rear ends, was because they were 2.5" narrower; thereby making it easier to install wider than stock tires on your car.
William

8.8" rear end questions

Reply #3
The 8.8 read housings between a stang and a tbird cougar are the same.  The difference is made up in the backing plates and the axles.
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8.8" rear end questions

Reply #4
I found that out from doing my search.  I'm just talking about these rear ends as a unit (as-assembled dimensions).  Instead of having to piece together a rear end that has the qualities and dimensions I want, I'd rather buy one that already has the dimensions and qualities I'm looking for.
William

8.8" rear end questions

Reply #5
I guess it depends on the rims that you want to put on the car. I have 235/55-16's on Mark VII rims and I have a ton of room on the inside and outside. If you're trying to run a rim with very little backspacing, then I guess you could run into problems, but the fronts are closer to the fenders than the rear, so you would have problems there first. I am more than satisfied with how easy it was to swap in the Mark VII parts. I even used the stock parking brake cables. I don't think you can do that with a TC rear. I don't know about the SN-95 parts so I can't comment there.
2017 Subaru Outback
2007 Lincoln MKZ
1990 Ford F250 / Banks turbo diesel

8.8" rear end questions

Reply #6
I have a Fox Mustang 8.8 housing and Fox length axles in my 83 Bird.  The tires are 275/35/17 on a 17 X 9 rim with a +24mm offset.  Now for a different comparison I have an SN95 width 8.8 under my Fox Mustang and it has 255/17/40's on stock 97 Cobra wheels (17 X 8 with a +30 mm offset).  The only reason I mention that one is that if the SN95 rear will fit under that car and clear the 255's it will do the same thing on a T-Bird with the right wheels.

If you have access to the SN95 rear then use it.  You will be able to use wheel spacers (1/16" thru 1/4", more than 1/4" and I would suggest longer studs) and offset to get the wheels and tires you want under the car with the only physical limitation being the wheel well itself and even that can be mini tubbed if you just have to have some W I D E ass tires on the car.

With all of that said, be sure you have the brake system handled if you are switching over to rear discs but as many of your posts as I have read I would think you already have all of that covered.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

8.8" rear end questions

Reply #7
Thanks for the good feedback Darren.  That's just the info I needed.  I've been kicking around the idea of running 255's up front and 275's out back on the Blackbird, but I want to be able to rotate the tires.
It's good to hear from someone who's swapped in an SN-95 rear and mounted 255's on it.  I was afraid of being faced with some kind of crazy back spacing issue.  Seeing that you've been there, done that, is a big relief.
Thanks again for the feedback.
William

8.8" rear end questions

Reply #8
Just to make sure, the SN95 rear is in my 93 Fox Mustang Coupe car not a T-Bird.  However, having the Fox Mustang rear in my 83 T-bird and having had a Fox Mustang rear in the Coupe I am 100% sure the SN95 rear will work in a T-Bird with the correct offset on the wheels and/or spacers.

Another note, I am running 17 X 8 with a 30 mm offset on the front of the Bird and I would not push anymore than a 245/40/17 on that wheel combo but I do have the SN95 96+ spindles up front which will push the tires out an additional 8mm per side so if I was running the 94-95 SN95 spindles a 255/40/17 would most likely work.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

8.8" rear end questions

Reply #9
Hey; thanks again for the feedback Darren.  That's gonna be good info to have when I'm ready to start doing all this.  I hate flying blind.
William

8.8" rear end questions

Reply #10
275/40/17s will rub the wheel wells with a Lincoln rear end.
I had to put air shocks in to keep from rubbing.


now it sits like this
[SIGPIC][/SIGPIC]
***** Project "EVOLUTION" 1987 Cougar LS  & 1985 Cougar Convertible *****
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5.0 HO 306 roller block, machined GT-40P heads, Wiseco dished forged pistons, Eagle forged floating I-beam connecting rods, Lunati pushrods, ARP bolts, Scorpion aluminum 1.6 rockers, Comp Cams Magnum 266HR, Explorer intake, 65mm TB, MAF Conversion, 19# injectors, Ford Racing stainless P-headers, 2-1/2" cat-less exhaust w/ Flowtech Afterburner lers , SC AOD with 2800 BDR torque converter, 3.73 T-Lok rear, CHE rear control arms, full 2-1/2" frame w/1" jacking rails & seat supports, Rear disk brakes, Turbine wheels, All original interior w/ floor shift upgrade .......
Pretty much every panel on my 87 is new, rebuilt, or re constructed. :D
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8.8" rear end questions

Reply #11
I was thinking about running 275's out back on my "Blackbird" (my DD '87 Sport with black side moldings), but I'm planning to run 255's on all 4 corners so I can rotate the tires.  It's a daily driver, so I want to get some good use out of whatever tires I mount on it.  My "Red-Winged Blackbird" though (black '88 TC with red stripe down both side moldings) is definitely gonna have some beefy meats hung on the back of it though.  I just might hang something wider than 275's on it (tweaking will be required of course).  My "Red-Winged Blackbird" received a V8 transplant mind you.

I like your car's stance by the way.  :)
William

8.8" rear end questions

Reply #12
I have zero room left in the wheel wells with the 275's in my 83.  If I rolled the fender lip and relocated the rear coil overs I might squeeze a 295 but its just not worth it to me.  A set of good drag radials in a 275 would most likely stick all rwhp the car has anyhow.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

8.8" rear end questions

Reply #13
If I roll the lips in the rear I will be ok I think. It barely catches the outer 1/2" of the tire....I will probably do that before I start any filling and sanding back there, just to be safe.
[SIGPIC][/SIGPIC]
***** Project "EVOLUTION" 1987 Cougar LS  & 1985 Cougar Convertible *****
[/COLOR]
5.0 HO 306 roller block, machined GT-40P heads, Wiseco dished forged pistons, Eagle forged floating I-beam connecting rods, Lunati pushrods, ARP bolts, Scorpion aluminum 1.6 rockers, Comp Cams Magnum 266HR, Explorer intake, 65mm TB, MAF Conversion, 19# injectors, Ford Racing stainless P-headers, 2-1/2" cat-less exhaust w/ Flowtech Afterburner lers , SC AOD with 2800 BDR torque converter, 3.73 T-Lok rear, CHE rear control arms, full 2-1/2" frame w/1" jacking rails & seat supports, Rear disk brakes, Turbine wheels, All original interior w/ floor shift upgrade .......
Pretty much every panel on my 87 is new, rebuilt, or re constructed. :D
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8.8" rear end questions

Reply #14
I was told to use the same size tire front and rear for rotation purposes,but,the tires are unidirectional,so,I thought it was basically pointless to do that,SO,I went with 275-40-17 out back, and 255-40-17 up front. I may go with 315's out back on the next pair of tires.....maybe. The 275's are pretty wide,and without the quad shocks,and,using 2 1/2 in tail pipes,no rubbing anywhere.
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