Fox 4-lug Rear Disk Conversion Parts List - Help

Discussion in 'Fox 5.0 Mustang Tech' started by rushcanuck, Dec 2, 2013.

  1. Hey, Im just wondering if Ive got everything needed to convert my 89' foxbody 5.0 to disk rear brakes. This is what Ive got Ive pieced it all together at the local auto parts store

    -Turbo Coupe Right/Left rear Caliper
    -Russell braided 10mm banjo bolt flex hoses
    -Banjo bolts
    -Turbo Coupe Rotors
    -Raybestos PGD347 rear pads

    -SVO 73mm Right/Left front calipers
    -Hawk HP+ front pads

    -SVO Master Cylinder (Because the Cobra was unavailable)

    Rear parking brake cables Im unsure of but I believe the raybestos number for a turbo coupe is BC93634 and BC93638.

    I know Ive got to find caliper mounts, Im gonna start searching junkyards. What other vehicles might I be able to get the Caliper mounts? rear disk explorers? Lincoln mk7? anything else? if I cant find one I may have to fab something up.

    As for a proportioning valve Im fairly sure Ill be needing one so Ill likely use a SSBC one.

    If Im missing anything any input will help me out, thanks.

  2. SVO MC is too large. your pedal will be firmer. Instead use a 94-95 GT/V6 1 1/16" MC. It's an easier swap than the SVO MC and more appropriately sized.

    The TC's front setup uses 60mm calipers, and the 1" 93 Cobra MC. Using the 73mm front calipers will require a slightly larger bore MC. The SVO MC is 1 1/8" and sized for the 73mm front/54mm rear SVO calipers. When using the smaller 45mm TC rear calipers, a compromise of using the GT's 1 1/16" MC should put you where you need to be.

    I would also recommend swapping out the booster as well.

    For the caliper mounts, the only car you can use is the 87-88 T/C. You'll need the axles as well since the brackets will push each side out 3/4". The way around this, using your stock mustang 4-lug axles, is to buy aftermarket brackets from North Race Cars to use stock lenght 5-lug axles with the TC brakes. A little pricey, but would also allow you to run 9" or wider wheels out back

    All stuff to consider prior to starting the project
  3. Been there and done that! With success! :nice:

    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, 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.
    When you install the axle assembly you will need to leave the bolts for the control arms only finger tight. Once the axle and all the control arms are in place, put jackstands under the rear axle and under the front A arms. Level the car as best you can while it is on the jackstands. Then and only then tighten down the control arm nuts and bolts to the factory specs. This assures that there is no preload to position the axle up or down, it is preloaded to normal driving height.

    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 for details and pictures.

    See 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.

    Turbo Coupe axle swap parts list:
    87-88 T-Bird Turbo Coupe Rear axle
    94-95 Mustang Master Cylinder with reservoir
    Brake line Adapter fittings
    3 line to 2 line brake fitting kit
    Proportioning valve, Wildwood 260-8419 Summit or Jegs
    Kit to gut the stock proportioning valve Ford Racing M-2450-A Summit or Jegs
    Reuse stock brake booster – no changes needed with the parts in this list
    73 mm front calipers from a 91 Lincoln Mark 7 (two calipers) local auto parts store
    Emergency brake cable parts: Summit or Jegs or Late Model Restoration
    79-92 Mustangs use: M-2809-A* Parking Brake Cable (need 2)
    93 Mustangs: use 93 Cobra Ebrake cables.
    All years use: M-2810-A* Parking Brake Cable (short cable that attaches to the parking brake handle)

    I recommend that you use reman calipers and use the calipers from the Turbo Coupe axle for cores to return. The parking brake mechanism and the caliper slides tend to lockup and freeze

    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.
    Fixing the added axle length problem:
    If the extra width is a problem for your wheel and tire combination, North Racecars makes some rather expensive brackets ($160 +) which allow you to use the stock axles. See
  4. Hey thanks for the reply.

    Okay, yeah I was hoping i wouldn't have to use the Big Grungy looking old school SVO Master Cylinder, I'll look into getting a 94-95 GT one instead.

    So even the Turbo Coupe mounts wouldnt work when using my stock axles? at the moment Im running 245/45R17 on a set of 17x9" American racing SC's, mainly the reasoning why Im trying to avoid swapping to a 5-lug.

    I thought that it would work to just slide the rotors over the existing axle ends and mount the caliper?

    As for a complete turbo coupe rear end isnt really doable on my end. Cost of shipping to up here in canada would be murder alone and the likeliness of finding a wrecker one is next to impossible
  5. If you stick with the stock 60mm front calipers, you can use the 1993 Cobra MC

    The offset is different. It's to allow the use of ABS rings on the axle just inside the rotor. Because of this, the T/C pushes the offset out 3/4". So if you go to a boneyard and grab TC caliper brackets, you will need the axles as well. This might cause some issues depending on rim offset/backspace.

    Alternative is to buy these brackets. They will use your stock axles and allow for the use of TC rear brake parts

    You want the 4-lug setup here. Brackets only