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1983 Ford Fox Body Mustang GLX Convertible
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Discussion Starter #1
Having trouble finding ways to find a good 8.8 rear end. Right now I have a trashed 7.5 rear end that sat for 7 years. Looking for good rear end swaps if yall have any good suggestions. Would an sn95 rear end fit into a fox body with little modification? Also I want good brakes that aren't big brakes or $1k. I won't be racing but I am looking to have a performance feel in the car. Later on I probably will make other performance mods, feel free to reply with yours.

Recently I got connector rails from maximum motorsports welded into the frame. Also planning to get coil-overs depending on the front k-member and rear end.

Feel free to spread suggestions.
 

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1985 Mustang
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SN95 94 through 98 8.8 rear housing is the same width as the fox body housing in your 83. The 99+ rear is wider. The axles on the SN95 94 though 98 are a .75in wider than the fox rear because they have the added abs ring, so that's 1.5in total. You can use the pre 99` SN95 with the wider axles in the fox. The 1999 and newer rear end is 3 inches wider than the fox so that's too much to just swap in.
Scrounger’s Guide - Ford 8.8 Rear Axle - Hot Rod Magazine

I just got an 8.8 for my 85 that had SN95 axles in it. I will be rebuilding with fox length axles, and i think i'm going to get "North Racecars" caliper brackets which allow me to use fox length axles and cobra disk brakes.

North Racecars IRS Cobra Disk Conversion Instructions
 

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1983 Ford Fox Body Mustang GLX Convertible
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Discussion Starter #3
SN95 94 through 98 8.8 rear housing is the same width as the fox body housing in your 83. The 99+ rear is wider. The axles on the SN95 94 though 98 are a .75in wider than the fox rear because they have the added abs ring, so that's 1.5in total. You can use the pre 99` SN95 with the wider axles in the fox. The 1999 and newer rear end is 3 inches wider than the fox so that's too much to just swap in.
Scrounger’s Guide - Ford 8.8 Rear Axle - Hot Rod Magazine

I just got an 8.8 for my 85 that had SN95 axles in it. I will be rebuilding with fox length axles, and i think i'm going to get "North Racecars" caliper brackets which allow me to use fox length axles and cobra disk brakes.

North Racecars IRS Cobra Disk Conversion Instructions
What springs and shocks you have? For SN95?
May do something similar and just find a housing and build the rear end.
 

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1985 Mustang
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For the rear you would use the same fox shocks and springs, not SN95 stuff. I have stock 85 springs right now and I'm still deciding what to use when I put it back in. I think I'm going to use the maximum motorsports lower control arms with adjustable spring perches, so I might just reuse my stock springs.

For the front I have 94/95 spindles. I still need to take the old control arms off and hopefully reuse with new bushings and ball joints. The car spent it's life going through Chicagoland winters so they're pretty rusty. If using the 94/95 spindles you can either use SN95 ball joints or the fox ball joints with a spacer between the nut and the spindle. The fox ball joint is longer and the nut will not tighten without the spacer or stack of washers.

I'm in the middle of all this so my answers are half research based vs actually accomplishments.
 

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I have an '86 Mustang GT 'vert that has had the entire suspension/brake treatment done a little at a time since the purchase in '90. The current set up is full MM suspension F/R, Cobra brakes F/R (soon F ST 40 4-pot with 14" rotors), running 18x11s with 315s all around. Street cruiser with some autocross and open track.

At this early stage I would recommend chassis stiffening first (FLSFC, STB, Lower G-load brace), especially if the car is a vert or T-top. These pieces help the vert/t-top cars reduce cowl shake and sagging doors, not to mention helping to remove suspension migration under load. Then I added Flowmaster cat-back, some poly bushings, better struts/shocks and FRPP "C" springs.

Next brakes. I put on rear discs early on using the old Ford M2300C kit which SSBC reproduced. This is a 4-lug kit that uses the same rear brakes as the 93 Cobra and 87-88 TB Turbo Coupe cars. Because my 86 had the small 10" front rotors, I upgraded to the 87+ GT spindles and 11" brakes. Together with the rear set-up, I had the same brakes as the 93 Cobra. The car stayed in this configuration for about 15 years. Motor was stock except for a K&N drop-in filter and removal of the filter box snorkel.

Later I went into the motor by replacing the stock heads with E7s, an upper intake and larger TB from 87+ V8s, and BBK unequal shorts. I also got into more suspension stuff with an MM PHB and eventually a PM3L set-up, front C/Os and 5-lug conversion using the same rear brakes with 5-lug rotors and the Cobra 13" front set-up. Because the 86 as the narrower K-member, I also used 03 Cobra front A-arms.

Now the car is a full-on Pro-tourer/Resto-mod. It has taken until June of 2020 to reach this point.

Good luck guys.
 

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Because the 86 as the narrower K-member, I also used 03 Cobra front A-arms
wow, I wasn't even considering using the SN95 A arms until i read your post. I've read some old posts on the topic now, particularly the one below. Now I'm thinking with my 85` it's a good idea. This car is going to be a street car, and more likely to see the drag strip than autocross. But, I need to rebuild the front control arms anyhow, and by the time I buy new ball joints and bushings I'm pretty close to just buying a set of stock SN95 control arms (looks like they are still under $200 vs the crazy price for stock fox arms). So this would net me .83" wider per side. Are there any downsides I'm missing? I have a set of 1999 16" 7.5" wide wheels I may use so that limits the width of tire anyhow. If I do go with 17" wheels it looks like 235/45/17 fit, at least I found one mention in the post below.

Let me try to lay it out in a simple format:

Control Arms
All fox arms are the same length 79-93
SN95 arms are 1.33" longer than fox
T-Bird arms are the same length as SN95 arms.

K-members
79-86 have control arm mounting positions 1/2" per side futher inboard than 87-93. 1" total narrower track width than 87-93.

mix and match (all compared to 87-93 stock track width)
79-86 stock K-member + fox arms = .5" per side, 1" total narrower track width
79-86 stock k-member + SN95 or T-Bird arms = .83" per side, 1.66" wider track
87-93 stock k-member + SN95 or T-Bird arms = 1.33" per side, 2.66" wider track
79-86 Schneider modified k-member (additional .5" beyond the .5" already build into the narrow 79-86 k-member) + SN95 or T-Bird arms = .33" per side, .66" wider track as compared to stock 87-93.

Spindles
96+ SN95 spindle is said to add .31" (8mm) of track width when replacing a fox spindle. I have not confirmed this.
 

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Well, the math works out to the total extra length the sn arms are over the fox arms. In my case, the sn arms were 1.25" longer per side than the Fox which means I gained 2.5" in track width total (1.25" per side). BUT, when compared to the later v8 cars, you lose an inch so back to 1.5" extra or about .75" per side (not counting the minor amount the spindle adds) when compared to the later v8 Foxes.

This is why it works so well without much fender modification if any. I never rolled my fenders but I did have to run an adjustable height C/O and 2* negative camber. This was with 17x8 Cobra wheels with 245/40/17s or 17x9 Cobra Rs with 255/45/17s. If you run a narrower wheel with about the same off-set as the Cobra wheels, you should be golden with the correct ride height

Not only does this extra front track width improve cornering, but you gain much needed negative camber which pretty much goes away, even with CC plates maxed out, when sn spindles are mounted on the stock a-arms attached to the stock 85 K.
 

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If your K-member is an 86 or older the SN control arms work better than the 87 up K-members because the control arm mounting points are moved inboard on the older K-members.
 

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Sorry for hijacking, but being that you guys have pre 87 cars, I need to ask...

I have the narrow 86 k-member and want to swap in sn95 stuff. So reading everything mentioned before, I need to run sn95 a-arms to get back enough negative camber, even with CC plates. How much track width does this add per side and will I have issues running 8 inch wide wheels and clearing the fenders without rolling them?

What MC are you guys using with sn95 cobra calipers? I have the smaller 96 cobra dual 38mm piston calipers and can't decide what MC bore size I need to work with the 95 v6 brake booster.
 

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I wanted to say it was like 3/4" wider, per side.
I think the 99V6 MC is 1" bore, and the 94-95 cobra is 15/16", you can double check that at rock auto to be sure. I've used both on conversions I've done, and they both work fine.
 

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So, the answer to track width total gained will be approximately 2.5" over stock using the sn arms and spindles with the narrower K.

On my '86 I initially tried to run conventional FRPP "C" springs with the sn arms, but that caused a lot of rubbing. This with 96 Cobra 17x8s with 245/45/17s. The reason was because the longer arms provide more leverage, lowering the car by another inch or so. I had to go to C/Os to raise it up (Bilstein HDs w/MM C/O conversion and 300# springs). This gave me the correct height but the wheel/tire package was still too close to the fender. So I bought the MM CC plates and added about -2* camber. With this configuration and at my ride height of 25-3/8" ground to lip, I did not have to roll the fenders. I ran this car in auto-cross and open track with no fender rubbing. I tried to lower it more but that required more aggressive negative camber than I was willing to run on a DD.

When I went to 17x9 95 Cobra Rs with 255/45 Hoosiers, I had to raise it up another 3/8" and run more camber. That became a hassle for each event so eventually just ran with 200 TW tires on the 17x8 Cobra wheels.

I originally ran the 93 Cobra M/C and stock booster with my Cobra brakes (actually, I had the SSBC rear kit which is the 93 Cobra/TB Turbo Coupe system converted to 5-lug). Now I have the 93 Cobra booster with the same M/C with the Cobra rears and about to install a Stop Tech 14" front set-up. This system seems to be good pedal fee/ as well as modulation.
 
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