1. What you have:

79-82 All (except 79 V8): 9.15" front disc, 7.5" rear axle with 9" drums. 4 Lug.

1979 V8, 82-85 all (except SVO), 86-93 4cyl: 10" front disc, 60mm single piston caliper. 7.5" rear axle with 9" drums. 4 lug.

1986 GT: 10" front disc, 60mm single piston caliper. 8.8 rear axle with 9" drums. 4 lug.

1984-86 SVO: 11" front rotors, 73mm single piston caliper. 7.5" rear axle with 11.375" rear disc brakes. 54mm rear pistons, 5 lug. Rear is 1.25" per side wider than 87-93. Same rear brakes as the Lincoln Mark7s.

1987-1993 GTs and LX 5.0s: 11" front rotors, 60mm single piston caliper. 8.8" rear axle with 9" drums. 4 lug.

1987-1993 Saleen Mustangs: Same as the SVO brakes -- 11" front rotors, 73mm single piston caliper. 7.5" rear axle with 11.375" rear disc brakes. 54mm rear pistons, 5 lug. Rear is 1.25" per side wider than 87-93. Same rear brakes as the Lincoln Mark7s. There were optional brakes on the SA-10 and SC cars that used the Alcon 4-6 piston 13" front brakes.

1993 Cobra: 11" front rotors (larger hat to match the rear offset), 60mm single piston caliper. 8.8" rear axle with 87-88 Tbird Turbo Coupe 10" disc brakes. 38mm rear pistons. 4 lug, different offset from GTs. Rear is .75" per side wider than GT/LX

Front Brake Upgrades for 1979-86 Mustangs and 1987-93 4cyls:

To upgrade the brakes on the 4 cyl, pre-'94 V6 or 1986 and older GTs, you will need new to upgrade the spindles and rotors. Consider if you are going 5 lug as the SN95 spindles would be the better option. Check my SN95 brakes page for help. If you want to stay 4 lug, then you will need the spindles and rotors from a 87-93 5.0L mustang to complete this along with new brake lines. Check this link for more info and all the parts needed.

2. Front Budget Brake Upgrades for 1987-1993 GTs and LX 5.0s. Also 1993 Cobra:

1.  Flush the braking system with new fluid! [how to ] Adjust the rear drum brakes.

2.  New performance brake pads (such as Hawk or Performance Friction brands)

3.  Upgrade the stock rubber caliper slide pin bushings to metal ones.

Reason being the stock rubber bushings let the calipers move during braking, so the pad doesn't contact the rotor squarely. This movement reduces braking effectiveness, and causes uneven pad wear from pad cocking under hard braking. You will not notice a lot of difference around town, but at highway speeds you can tell the car slows down quicker. [ installation info] These bushings work on the stock calipers and the SVO 73mm calipers, but not the newer SN95 calipers.

4.  Upgrade the front calipers to 73mm SVO units. 

Get the 73mm calipers with a steel piston if you can. They are usually denoted in the part numbers with a "S". If not the phonemic will work fine on the street. Get the calipers for a '91 Lincoln Mark VII for a direct bolt in (other 86-91 Lincoln's should all have the 73 mm calipers, 86-91 Crown Victorias and 84-86 SVO 4cyl Turbo Mustangs). Here are the part numbers the remanufactured Bendix parts:

Left caliper : R55247S
Right caliper: R55246S

5.  Change rotors to a slotted, drilled and/or dimpled units. Be sure to put new metal caged bearings in the new rotors! There is debate on the effectiveness of slotting and drilling, so do it more for the looks than performance gains. If anything the slotting and drilling will lessen the weight of the rotor and rotating mass.

6.  Upgrade the stock rubber brake hoses to Stainless Steel Brake lines.

Stainless steel hoses provide better performance than the stock rubber hoses because rubber will expand, causing a spongy brake pedal and even some loss of initial braking force. Installation of the SS hoses will give your Mustang a firmer pedal, quicker braking response, and easier brake modulation. The best place to purchase these is from Maximum Motorsports . They will fit perfectly, other brands may require modification to the brake line bracket.

For custom conversions, especially the rear with different sized fittings than a stock SN95 car, you can get custom units made for you. By far the best place for service and price that I have found is Paragon .

Brake cooling for a track car is available. CobraAutomotive has a kit for the 11" front mustang brakes. This is for the older 11" Mustang brakes, like 60-70s era, but could be adapted or used as a template to make your own.

Baer and Wilwood make a 4 & 5 lug kits up to 12" and 13" rotors for the fox body Mustangs like the SN95 and 94+ Cobra brakes. Also SSBrakes makes some larger Force 10 4 lug kits. Keep in mind that if you use a modified 87-93 v8 spindle for these conversions, you will limit your wheel selection.

Most other upgrade options will cost more money since you will have to convert to 5 lug wheels. You would be better off getting the parts, wheels and tires off a wrecked SN95 GT, V6 or Cobra and swapping parts. Otherwise buy a complete kit front and rear like the FMS M2300K kit. Take off wheels and tires from the new Mustangs can always reduce some of the wheel/tire cost.

Get new shoes and adjust them up. Also replace the stock center axle rubber line with a stainless steel line. Other than that, you can swap to 10" rear drums. But you would be better off swapping to rear disc brakes. The rear disc will help your stopping distances slightly, decrease brake fade and increase the pedal feel and modulation.

5. Rear Disc Upgrades: '87-88 Ford ThunderBird Turbo Coupe/'93 Cobra Rear Disc Brakes:

These are 4 lug 10" vented rotors. This is a great swap if you can find the whole rear end! It is a 8.8" rear end, and the stock gear ratio is 3.55 for the manuals, 3.73 for the autos on the Turbo Coupes, and 3.08 on the 93 Cobra. Keep in mind the axle is .75" wider than the stock Mustangs, you will need to adapt the brake lines fittings. The easiest way is to use the drum brake rear hardlines and adapt at the caliper softlines. You need to drill the quad shock mounting holes 2" lower on the T-bird axle for the Mustang. For E-Brake cables, you need to purchase use the FMS cables. If you have a '93 vintage, you need to use the '93 Cobra cables. Ford made the '93 E-Brake cables like the Sn95 units with a center mounting in the tranny tunnel. 93 Cobra E-Brake cable #F3ZZ-2A635-A.

If you cannot get the whole axle or do not want it, get all the brake lines, calipers, bolts, rotors and axles. Then swap this into your existing axle. Here is a parts list that you need to do the swap from the '87-88 Thunderbird Turbo Coupe or '93 Cobra:

• 10" 4 lug vented rotors
• rear calipers
• rear caliper brackets
• Axles -- if you use the stock caliper brackets. They are 3/4" wider than the stock '87-93 units.
• soft brake lines
• (2)FMS M-2809-A ebrake cables for '87-92 cars, '93 Cobra units for '93 year cars
• (1) FMS M-2810-A center Ebrake cable
  
• FMS M2450-A proportioning valve solid end cap
• Adjustable proportioning valve
• new 2 port 4 wheel disc master cylinder (1" bore for stock front calipers or 1 1/16" for the 73mm fronts)
• 3-2 port master cylinder conversion. $25.00 shipped
• 2 adapter fittings to use the stock drum brake hardline with the softlines, $10
  

The discontinued Ford M-2300-C kits uses the same calipers and rotors from the 87-88 Turbo Coupe, but stock length axles. SSBC and other companies have picked up this Ford kit and sell them for about $600. If you can get the calipers and rotors, but not the axles or axle brackets, call North RaceCars for these brackets! These will allow you to use the stock length rear axles with the TC rear disc parts!

Here is what I have done for the rear: I bought some custom rear brackets that use the Ford ThunderBird Turbo Coupe 87-88 rear rotors that are 10" vented 4 lug units and Cadillac rear calipers from a 80-85 Seville. This is a very similar way to make a conversion like what is offered by Master Power Brakes, ECI and BM for hotrods. These calipers have built in parking brakes, a 54 mm piston available in steel, aluminum and phonemic, and are readily available in junkyards. You can get the brackets from SteelTechSoutions Inc or search on Ebay for "rear disc" and you will see them listed. Use yoru stock 87-93 4 lug axles for the stock rear track or the 87-88 Turbo Coupe/93 Cobra 4 lug axles if you want a wider rear offset.

Here is the parts list and prices that I got to give you an example of what is needed:

-Custom rear brackets
-'87-88TC/'93 Cobra rear Rotors; 4 lug
-Rear calipers from 85 Cadillac with all lines, springs, pins, etc: The casting numbers on the calipers are 020 and 021. This is an easy way to determine if they are the correct units.
-New Pads
-2 x 3/16" couplers - or use the TC rear softlines with adapters
-Adjustable proportioning valve
-FMS M-2450-A plug for the stock PV
- Brake fluid
-cable ends to shim the stock parking brakes -- or use the FMS M-2809-A cables
-rear soft lines from 87-88 TC

Why Cadillac Calipers? Well for one that is what the brackets are designed for and you can get the brackets. I know that it is hard to get SSBC to sell you just the caliper brackets. You can use your stock axles. You have the choice of 4 or 5 lug. There are a lot of 80s Cadillacs in the junkyards to pull the calipers from. You can modify your stock parking brake cables to work with the calipers. The stock brake lines bolt directly to the calipers. They are a large piston compared to the Ford rear calipers. You can run 4 lug plus 5 lug with the same calipers. You can run different axle offsets. Lastly, they use the same pads as the front GM Metric calipers. So you have a wide selection of pads making them are cheap and plentiful in parts stores!

***If you are using Cadillac ElDorado/Seville rear calipers there are some important things you should know. One of the biggest advantages of a disc brake system is the fool proof self adjuster. Not so with this rear GM system. The rear calipers adjust off the parking brake. The parking brake is incorporated into the caliper. You must set the parking brake every time you park the car . The rear caliper pitons utilize a one way clutch inside the caliper piston. When the parking brake is applied the clutch senses when there is .030" or more clearance between the friction material and the rotor on the inboard side. When there is more than .030" the clutch turns inside the piston adjusting it out keeping the rear brakes adjusted. If you do not set your parking brake every time you will start to lose brake pedal (low and spongy) and the adjuster mechanism will not work any longer. Also: never use rebuilt calipers on the rear because the rebuilders use the old pistons and the pistons were the reason the caliper failed in the first place. If you do, get a lifetime warranty on them like at Autozone!

Check my link for installation notes.