Bake conversion questions

Brake / rear end conversion questions

This isnt for me, but my uncle... he has an original 4 cyl mustang (1988) that hes put a 460 into, and has a spare turbo coupe for parts that hes using. hes taking the rear end out of the turbo coupe thunderbird and is converting the rear end to it since the turbo coupe has an 8.8 and he only had a 7.5 rear in the stang. he called me asking about the master cylinder and if he has to change it out to one from a car that didnt have anti-lock brakes, or if he had to do something to the proportioning valve in the master cylinder. if anyone has any ides or can point me in the right direction, id really appreciate it.. thanks in advance!
 
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I have a 79 with a 460 in it. Switched the complete rear end and front brake setup out of a wrecked 96 cobra. Still using the original master cylinder and prop valve from the old 4cyl 79 to power the 96 brakes. Works fine for the manual master cylinder it is.

If anything the prop valve would need to be changed, but the master cylinder should work fine with that.
 
chaka said:
I have a 79 with a 460 in it. Switched the complete rear end and front brake setup out of a wrecked 96 cobra. Still using the original master cylinder and prop valve from the old 4cyl 79 to power the 96 brakes. Works fine for the manual master cylinder it is.

If anything the prop valve would need to be changed, but the master cylinder should work fine with that.

cool... so he should be able to use the stock 4 cyl master cyl without switching to a different one? or without adjusting the proportioning valve?
 
TrickFlow306 said:
cool... so he should be able to use the stock 4 cyl master cyl without switching to a different one? or without adjusting the proportioning valve?

It will stop him for sure (as long as he runs everything right)

But the proportioning valve is still wrong and should be looked into I know my car stops with the 79 master cylinder and the prop valve, but I am going to look into an adjustable prop valve to fine tune it.
 
Turbo Coupe rear end in a Mustang

Been there and done that! With success! :nice:

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.

Auto trans Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. I choose 3.55 since I do more highway driving.

You will need a several sets of fittings, I recommend that you get them from Matt90GT's website, http://www.svo73mm.cjb.net/. 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 8 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.

All in all I have been very pleased with the results.
See http://www.mustangcentral.net/tech/brake.html for help with the emergency brake - the stock setup tends to lock up and not release properly.
 
The only fitting I needed to make was on my 82 Capri. The brake line runs down the right side of the car. I had to make one line to carry the brake line to the middle of the car. Then I used the stock mustang center brake line to chassis mount. I made a one line to connect the stock T-bird line to the Capri's stock lines.

Allen