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Possible to convert thunderbird rear disc 8.8 to 5 lug?

  • Thread starter Thread starter Bigstang1
  • Start date Start date Jul 19, 2008
B

Bigstang1

Founding Member
Aug 28, 2002
415
0
16
Massachusettes
Jul 19, 2008
#1
  • Jul 19, 2008
  • #1
I bought a roller recently and it has a super or turbo coupe rear end in it with stock rear disc. Is there a rotor that will fit these calipers that are 5 lug?
 

jrichker

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Jul 19, 2008
#2
  • Jul 19, 2008
  • #2
Five lug Turbo Coupe conversion:
Use the 94-95 axles Mustang axles. Use 1990 Mazada MPV 3.0 V6 front rotors (10", 5 lug x 4.5" pattern, 2 7/16" offset ). While you are at the auto parts store, set a TC rear rotor side by side with the Mazada rotor and they are the same except for the offset.

The next step fixes the offset problem:
Use a Maximum MotorSports 1/8 spacer (MMWS6, Maximum Motorsports :: The Leader In Mustang Performance Suspension ) between the inside of the rotor and the axle flange. The spacers may need to have the OD machined to fit properly. The stock rotor offset is 2 5/16" and the Mazada rotors are 2 7/16" offset. The 1/8" spacer puts the rotor back dead center alignment with the calipers.

Be sure to do the basics first...

Been there and done that! With success!

Do the 87-88 T-Bird Turbo Coupe rear end swap!

Auto trans 87-88 Tbird Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. Cost is $125-$300 for the rear axle. Add another $100-$200 or so to complete the brake upgrade.

I choose 3.55 since I do more highway driving. Both ratios have 10 5/16" disk brakes with vented rotors as standard equipment.

It takes 2 guys the first day to get the old rear end out and the new one bolted in place. It takes 1 guy another whole day to do the brakes.

You will need a several sets of fittings, I recommend that you get them from Matt90GT's website, 87-93 Mustang 5.0 Brake upgrade pages. Improve your 60-0 times!. Read Matt's instructions thoroughly, everything you need to know about the brakes is all there. You need to be patient and follow all the internal links, and there are many of them. You will need 2 fittings in the rear to adapt your old brake tubing to the TC disk brakes. The fittings go between the steel tube and the caliper brake hose. You will need another set of fittings to make a 2 port to 3 port adapter. To make life simpler, just buy the kits from Matt. You could piece them together, but it's not worth the time unless you work at an auto parts store with all the fittings ever made.

You will need to drill the quad shock mounting holes 2” below the holes drilled for the Turbo Coupe mounting points. The bolts are metric, so don’t loose them or the nuts. A 15/32” drill should be about the right size unless you have access to metric sized drill bits. Going without quad shocks is not an option unless you have aftermarket parts to soak up the wheel hop.

You will need a proportioning valve, Summit has one for $40 + shipping.
You will need a kit (FMS makes the part) to gut the stock proportioning valve, Summit also has that, about $10.


You will need a new master cylinder, see Matt's site and make you choice. I used a 94-95 Mustang master cylinder. Note that rebuilt 94-95 Mustang master cylinders do not come with a reservoir. That means a trip to the junkyard and some more money spent.

Your brake pedal may be very hard and almost impossible to lock up the brakes. I had to replace the front calipers with 73 mm calipers from a 91 Lincoln Mark 7 to get the braking performance up to par.

Bleeding the brakes will require 2 people and some coordinated effort. I don’t recommend using you wife or girlfriend to pump the pedal – they get offended when you yell at them. I used a homemade power brake bleeder constructed from a garden sprayer and some fittings from Home Depot. It cost about $25 and was worth every penny. See how hard is it to bleed brakes? - Mustang Forums at StangNet for details and pictures.

See Mustang Central.net FMS M2300K Brake Install for help with the emergency brake. The red words link to some very useful photos on how to modify the handle. The stock setup tends to lock up and not release properly.
All in all I have been very pleased with the results.

Identifying a Turbo Coupe rear axle:
1.) Measure the rotors - a TC disk brake uses 10 5/16" vented rotors.
2.) Measure the length of the quad shock mount arm and compare it to the mount on your existing stock axle. The TC quad shock mount arm is about 8" long if I remember correctly.
3.) Measure the distance between the axle flanges and compare it to stock. The TC rear axle assembly is 3/4" wider per side, or 1 1/2" wider for both sides.
 

LiquidGT

Member
Oct 8, 2007
368
0
16
Near STL hell
Jul 19, 2008
#3
  • Jul 19, 2008
  • #3
Not to jack the thread, but I have a TC rear that needs to be put in also. Anyway I always wondered if you can use the North Racecars brackets and fox length axles with the MVP/spacer set up? It seems like it would work, I just want to see if anyone knows before I try it myself.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,944
224
Massachusetts
Jul 19, 2008
#4
  • Jul 19, 2008
  • #4
It should work. You just need to still use the spacer.


I'd recommend upgrading the studs with this method. It's just added insurance since you are sandwiching a rotor and spacer between the wheel and axle flange. It's $20 for a little extra safety.
 

Adams91LX

Active Member
Dec 9, 2003
689
12
29
Plano, TX
Dec 18, 2010
#5
  • Dec 18, 2010
  • #5
Or... another thought...

pick up the breeze automotive rear TC rotors re-drilled for 5 lug....

then take to machine shop for a small enlargement of rotor hat

swap 94-98 axles in...

enjoy.
 

giddyup306

Founding Member
Oct 22, 2002
3,041
2
59
Dec 18, 2010
#6
  • Dec 18, 2010
  • #6
Bigstang1 said:
I bought a roller recently and it has a super or turbo coupe rear end in it with stock rear disc. Is there a rotor that will fit these calipers that are 5 lug?
Click to expand...

There is a difference between a SC and a TC. Which one is it?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,260
17,944
224
Massachusetts
Dec 19, 2010
#7
  • Dec 19, 2010
  • #7
It's been 2 years....I am sure he has found out by now
 
1

1990MustangLX50

Member
Jul 11, 2007
89
0
7
Dec 19, 2010
#8
  • Dec 19, 2010
  • #8
giddyup306 said:
There is a difference between a SC and a TC. Which one is it?
Click to expand...

the Super Coupes with the blown 3.8 V6 had IRS rears not solid axles, only the Turbo coupes came with the 8.8.
 
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