Hello people,
I have just taken a look (and some pictures) at restoring my pedal box and everything that is attached to it.
This caught my eye and I am wondering how many problems you guys see.
I have not touched anything yet at the moment I took this picture, just took it out of the car few years ago and today put it on a stand to start the restoration.
Meanwhile I know I'm in need of a new brake master cylinder, what is the recent status on OE replacement?
Jochen
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The dust boot is missing on the clutch master. The retaining clip and washer for the gas pedal are absent. It looks like you do not have the clutch effort reduction systems and that's one less thing to worry about. Overall it looks healthy. I can't comment on the reproduction OE brake master cylinders since I am using the Ford master along with an adapter.
Do you know the bore diameter of the stock style master?
23 mm, anothers links for the same brake master cylinder :
* 308 / 328 / Mondial Brake Master Cylinder -133576 23mm | AW Italian Auto Parts
I have found mine to be 25.4mm.......
Wow Steve, that looks neat. In some time mine will look like that too, with some modifications. ;-)
The clutch master dust boot is missing because they added a spring there since the original spring was broken in its place.
And what do you think of the solution for the missing clips at the brake pedal to the booster?
Love the ziptie holding the pin into the brake booster shaft! ''
Ron
"The clutch master dust boot is missing because they added a spring there since the original spring was broken in its place."
That spring belongs there, and there is a dust boot available as a part of a rebuild kit that fits perfectly.
Someone here helped me locate it. I'll look.
Here it is on Ebay. The dust boot is the only part you can use, the rest is not simpatico. Too small.
when do you say 25.4 mm is for the mustang one ? because, if I do not make mistake, the original pantera was a bentitalia brake master with a bore diameter of 22 mm on the first versions and 23 mm on the last ones. on my 79 euro GTS I had a 23 mm bore.
"I have found mine to be 25.4mm......."
That's an even inch. The ford and chevy masters that I have seen adapted are, I think, 15/16", or about 24mm, and the stock appearing style master is 23mm.
Is there an optimum size or is it about personal preference? Either the shorter throw and harder pedal of a larger bore, or easier pedal, but longer throw from the hydraulic advantage of a smaller bore?
@larryw posted:"The clutch master dust boot is missing because they added a spring there since the original spring was broken in its place."
That spring belongs there, and there is a dust boot available as a part of a rebuild kit that fits perfectly.
Someone here helped me locate it. I'll look.
Here it is on Ebay. The dust boot is the only part you can use, the rest is not simpatico. Too small.
Oh, my mistake, I thought (how could that be) that it was a work around solution for the broken spring at the clutch arm.
@dipascale posted:when do you say 25.4 mm is for the mustang one ? because, if I do not make mistake, the original pantera was a bentitalia brake master with a bore diameter of 22 mm on the first versions and 23 mm on the last ones. on my 79 euro GTS I had a 23 mm bore.
I will measure again tomorrow.
Confirmed it is 25.4mm ergo 1". 
@larryw posted:"I have found mine to be 25.4mm......."
That's an even inch. The ford and chevy masters that I have seen adapted are, I think, 15/16", or about 24mm, and the stock appearing style master is 23mm.
Is there an optimum size or is it about personal preference? Either the shorter throw and harder pedal of a larger bore, or easier pedal, but longer throw from the hydraulic advantage of a smaller bore?
I have both. As far as preference, I don't like the 1 1/8". There is less progression, and the pedal is much harder.
"I have both. As far as preference, I don't like the 1 1/8". There is less progression, and the pedal is much harder."
Other than the master cylinder bore diameters, are both cars otherwise set up with stock or similar calipers?
If I did the math right, bore area of the 1-1/8" master is just about 1 square inch, and the area of the 22mm (7/8") master is about .60 square inches. A pedal throw of 2" with the larger master, would become 3.33" with the smallest. That is pretty significant. No wonder the hard pedal.
The 15/16" bore would require a 2.89" pedal throw to move the same volume of fluid, that is close enough to the 22mm bore throw (and easier pedal) for me.
Everything is the same, stock setups. 22mm is pretty small. 23-24 is what I would shoot for if you want the feel of a modern day car.
The size of the bore effects the effort needed to the pedal.
The Mustang varies, depending on application from 7/8" to 1" in 1/16" increments.
By far the most common application is 7/8" as it is the easiest to operate.
Here in the US, the aftermarket is going to deal with SAE dimensions and many are using Ford Mustang masters (with adapters) as aftermarket replacements for the original Euro metric units so I refer to them for that reason.
Where you start to change the piston diameter is when you go racing.
I have gone through an entire step by step trial of each BY 1/16" INCREMENTS and can tell you the results. The ones I skip here are insignificant.
The 1-1/8" first came to light in the Boss 302 chassis modification booklet prepared by Ford.
It was used when you went to fully manual brakes, with the 67 Thunderbird front calipers and adding rear disc brakes.
Under that circumstance, it works fine. What happens is that it reduces the pedal travel and also the ability to fully lock up the brakes.
When you go back to a more standard brake arrangement WITH POWER BOOST ASSIST you can't operate the pedal.
The original application of the 1-1/8" is from a Ford truck.
The advice from me on this size is stay away from it.
The standard 6 cylinder bore is 7/8". That is the one with the least effort BUT has the largest ability to lock the brakes up in a panic stop. You don't want that in a performance application. PERIOD,
The 15/16" is the one that you are going to find in the factory performance packages and the Pantera. They are a compromise between effort and anti-lockup potential.
The replacement Master that I got from Hall, is an aluminum Ford Mustang unit (polished with the Hall 'bling') and is 15/16". It's fine.
My 68 GT350 is set at 1" (25.4mm) and is fine for the bigger then stock (68 Trans Am legal, 4 piston calipers, 1.25" thick vented rotors, 12" diameter rotors, rear disc brakes). As Kar Kraft put it, "they were designed to stop a 7,000 pound car. in a 3,000 pound car, they are fantastic".
I did just put those brakes on my Pantera and suspect that I MAY need to go to a 1" bore master to reduce lock up tendency but can't answer that one yet. That has not been determined if a change is needed there.
So the 15/16" master = 23.8mm which I would substitute a 24mm master as a stock replacement.
Forget about using the 1-1/8. You won't be able to move the brake pedal to stop the car. Don't waste your time with it.
The largest that you should attempt to apply in my view is the 1" of which there is no metric equivalent at 25.4mm. The 24mm should be what you want on a street car.
Thanks for the insights and knowledge.
Since I am going for non original calipers, and I have the donor master brake cylinder, I was happy to find that the bore of the master cylinder that is on my Pantera is the same as the donor's.
But I will have to find a replacement since the bore is pitted. I am investigating if the master of a Ferrari 400 can be used.
