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Topic: Master cylinder verification (Read 170 times) previous topic - next topic

Master cylinder verification

From what i read, for a pbr dual piston brakes and rear disc sn95 setup on a tbird, i need to get a master cylinder for a 93 cobra with a brake booster.  Am i correct, and is there alternative master and booster combo that could work

Re: Master cylinder verification

Reply #1
You need a master cylinder with a 1" bore.  Typically everyone gets the 93 Cobra unit as it has a 1" bore and the Cobra booster pretty much just bolts up to the existing holes in the fire wall.

You can use the MC and booster out of a 94/95 GT Mustang or the MC and booster out of a 94-98 V6 Mustang.  The issue with either of these is the booster has a different bolt pattern so you have to drill a couple new holes.  Pain in the ass, ask me how I know.  The MC is a 1-1/16" bore but they work fine.

So, my suggestion would be to run the '93 Cobra gear as it makes life a lot easier.  Either way you go you will need the following:

3 to 2 kit (to take your existing 3 port MC to a 2 port design)
Manual adjustable proportioning valve
Stock combination valve plug kit - used to gut the proportioning side of the combo valve (have to do this to make the manual adjustable proportioning valve work correctly)
Brake adapter fittings - you can use these or build your own lines with the correct metric fittings (pain in the ass)

To to recap, you will need the booster and MC for a '93 Cobra, a 3-2 kit, a manual adjustable proportioning valve, and a stock combination valve plug kit to install the MC with metric threads.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD

Re: Master cylinder verification

Reply #2
I thought you can also run an MC from an 85 lincoln towncar. Those only have 2 ports; front and rear.
1986 Ford Thunderchicken, 5.0 AOD w/ Shift kit,  354,XXX miles. 1-Family owned. Original engine+trans.
8.8 Disc Rear w/ 3.73 Posi. CHE Control Arms. '04 Cobra brakes all around. 2000 Cobra R wheels. Tubular front LCA's. MM Steering Shaft. Unlocked Speedo, Lowering springs, Eibach sway bars front and rear. Ram air intake.

Re: Master cylinder verification

Reply #3
Rock auto had the master cyl and booster available, i purchased it, plus i make my own brake lines, i have a donor 98 mustang gt, i will try the stock combo valve on that first since im using stock brakes, if i dont like it, ive used cpp adj proportioning valves before on a 65 mercury comet i had, on that i had quad piston brakes on the front and stock drums on the rear with no booster and could lock up all 4 wheels

Re: Master cylinder verification

Reply #4
The '85 Lincoln TC MC is a two port design MC with SAE threads and a 1" bore so yes you can use it.  It is a direct replacement for the 83-86 cars being the MC is SAE threaded on these cars but some do not like it due to it having the look of well an 80's car.  The '87-'88 cars moved to the same MC's as the '87-'93 Fox Mustangs which is a three port design with Metric threads and a 7/8" bore.  The '93 Cobra is a three port design with Metric threads and a 1" bore and is more modern in its design and appearance.

I will say that the original '85 Lincoln TC MC is aluminum and can be had for a whole lot less money than the '93 Cobra MC especially if you get a remanufactured one.

I have trashed brake lines trying to get a stock combination valve off a car.  Sounds like you have done this kind of work in the past so just take your time and use lots of PB Blaster or the like a day or two ahead of time.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD