Dual master cylinders

I have the same wilwood setup 4 piston 12" rotors and Wilwood recommended 1" front, 7/8 rear and 3/4 for the clutch. Installed their pedal setup also. No booster.

Ron

How did the installation of the pedal assembly go? How is the pedal pressure? What about the gas pedal?

Thanks,
Mark

Hi Ron,
Do you have some pictures and/or partnumbers?
And what is the diameter of the caliper pistons?

The installation required some fabrication for the height and left to right location of the pedals in coordination with the columns and dropped floors.

The brakes I purchased the calipers and rotors and fabricated the mounting brackets of steel. The axles are Mark Williams solid forged steel.

Gas pedal a steel bracket was fabricated.

The entire assembly was made to facilitate a fuel cell in the front compartment which is presently being made by ATL locally.

I'll try to post a few pics.
Ron

My calipers are:

Front: Wilwood 120-7429 1.75" pistons & 1.25" rotor width.

Rear: Wilwood 120-7431 1.38 pistons & 1.25" rotor.
Mark

Hey!? ,
I bought the same 120-7429calipers on Ebay. And I took a disk set from the 1990-1996 Pantera and machined them down to 310mm witch is a bit over 12”( the absolute max for 15”rims).

If you are using stock wheels you might have to file the outer edges of the calipers a bit in order for them to fit.

OK, I’m new here to the forum.
Purchased Pantera 4384 about a year ago & have been doing a lot of tidy up work to bring it up to a reasonable standard.
In regards to brake set up.

Obviously we are limited to the size rims we are using & the disc rotor diameter that can be fitted.
At the moment I have 15x13" rear rims & 15x10" front rims so I'm limited to rotor diameter.
But while I had the car on the hoist rebuilding & converting the rear uprights to taper rollers I decided to upgrade the rear brakes.
I had already thrown in the bin the front & rear standard proportioning valves & upgraded to stainless braided #3 brake hoses.
Front brakes were locking up way before the rears were really getting a chance to work & a lot of front nose dive, (has QV1 coilovers).
So I fitted Wilwood 12.1 diameter rear rotors with alloy hats.
Hats fitted to the outside of the axle hubs for ease of disassembly.
Used 4 piston Wilwood calipers.
Then took it for a test drive.

Because of the extra piston area on the new rear Wilwoods I had a lack of fluid flow to the rear brakes.
The result being the rears were no better than the old single piston brakes.
So I needed a larger bore master cylinder to push more fluid volume.
I was a bit concerned this would make the pedal too hard but one step at a time.
Upgraded the master cylinder to a 1 1/8" Wilwood duel cylinder.
As predicted, I gained volume, brakes worked much better than the originals & the car braked nice & level, but now had a hard pedal & a lot of effort required.
So next stage was a dual diaphragm 8" stainless brake booster.

Made up a two piece alloy adaptor plate to adapt from the Pantera 3 hole pattern to the new boosters 4 hole pattern.
Test drive & the pedal was much better, not much effort required & I could lock the rears before the fronts.
Not a desirable situation but on the right track.
Next step I installed a Tilton brake proportioning valve to the rear brake line.
The lever type so it’s easier to tune in & know the setting you have selected, (the dial type is too hard to know where you are as you have to count the turns every time you set it up).

Done some brake tests & set it up so on mega hard braking the fronts lock up just before the rears.
Car stays nice & flat under brakes & stops much quicker than the originals.

Once I can afford bigger wheels I will upgrade to larger front rotors & six piston calipers.
Right now my limit is the tyres, which are a few years old & the compound is harder than modern tyres.
Sorry for the long post.

Edge,

Thanks for your comments.I have gotten my brakes working again using a vacuum pump. I might just explore using your final solution.

Thanks,
Mark

Forgot to mention.
I also made a Vacuum bottle under the front hood next to the brake booster.
So I have the original vacuum line from the engine, then an Earls check valve & feeds into the bottle.
Bottle is just an alloy spun tube, similar to what an aftermarket radiator overflow tank would look like.
Out of the bottle another line goes to the check valve on the brake booster.
I needed this as I found on emergency braking the engine wanted to stall.
The booster was sucking all of the engines vacuum.
The Vacuum bottle fixed this issue.

regards, Tony.