Reply to "Dual master cylinders"

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.