[iceman36]

Dual Master Cylinder Brake Pedal with Balance Bar

I have an old 1936 Ford Panel Truck that uses an under floor brake setup. I can see 2 options for the Brake system.
1: under floor with boost or under floor with Dual Master Cylinder Brake Pedal with Balance Bar with out boost.
2: Dual Master Cylinder Brake Pedal with Balance Bar under Dash with out boost.
Has anyone out there ever used the Dual Master Cylinder Brake Pedal with Balance Bar system in an old vehicle before?
I was wondering how it would compare to a boost type system, I don’t want to have to stand on the brakes to stop or end up with my face on the inside of the windshield. I know the braking force is related to the Master Cylinder Piston size and pedal ratio and other factors but I have never actually put by foot on one to compare the two types.

Mike

[S10xGN]

Mike,

I can't help you as far as pedal effort (yet), but here's a pic of the mockup in my '47 Ford coupe. This is a Wilwood 340-5181 dual M/C reverse-swing pedal assembly with 6.25:1 ratio. I'll be using a 7/8" bore up front and a 1 1/8" bore for the rear because (due to my ignorance) I used front calipers for both front (2 1/8" piston) and rear (1 5/8" piston) systems.

There is another option for under dash that can use a power booster, Kugel's 90 degree mount unit, but it uses only a single M/C.

Russ

[iceman36]

Russ

I would be interested to know how it turns out. You are a little further along than me but where thinking along the same lines with Wilwood and Kugel except I was thinking about adapting a Dual Master Cylinder Brake setup based on Kugels 90 Deg. setup and Wilwoods 60 Degree Balance Pedal Assemblies.

Mike

[427v8]

Dual masters are no different than a normal master pedal feel wise.

Properly designed a manual system will be just fine, but a manual disk system will always require some effort. They are usually designed for 100lbs of pedal pressure to get 1g of stopping force.

keith

[h0trod389]

we used a dual master unit like the one your talking about in a pretty nasty 26T we built at our shop, its got about 600++ hp willwood disc on all 4.
it got away from me one time and i had to slam the brakes, and it woulda stopped on a dime if it wasnt running 3" fronts and 15" rear meats!

it came to a controllable stop/slide and all was safe!

i dont like booster type braking systems because it robbs vaccume!
and if you CAN run a booster, you dont have enough cam!

that master will work just fine with the correct check & proportioning valves!
Brian

[iceman36]

Thanks I have not taken any measurements yet or run any numbers.
But from what I can see the brake pedal will be longer than most setups which should give me more leverage.
So if I run the numbers using what I do know and play around with different pedal ratio, piston sizes and travel. I should be able to chart some design setup then do some CAD drawings and run it by Willwood before I start fabricating and spending money, companies usually work with you when you’re spending a couple grand or more.
I don’t think this 3000lb gorilla will ever get away from me like your 26T but slowing it down has to be on the top of my list or I could be on top of something else at the bottom of the hill.
I have been out of the loop with doing the 9 to 5 and raising a family so any help is greatly appreciated.

Thanks Mike

[Triaged]

Originally Posted by iceman36

...So if I run the numbers using what I do know and play around with different pedal ratio, piston sizes and travel...

I posted a spreadsheet (that I got from someone else) on a recent post from S10xGN. That might help you get the sizing right without too much time spent.

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