1962 Pontiac Consort Brakes question.

[Donnie]

Well right now the only mechanical issue I can't figure out is with the brakes. I wanted to upgrade the stock single res.power unit with a double res. cylinder. Me and my parts guy got in a book and found that a 66 would bolt up and it did.
Being that I had never done this before on a GM car he told me that I shouldn't need a proportion valve that I could just run a line from the backof the master cyl to the front brakes and a seperate line from the font of the cyl to the rear brakes.
I think he may have been worng. The car now has great back brakes and hardly any presure to the front. The is zero air in the system and EVERYTHING is new.

[Riff Raff]

You most definetly need a proportioning valve. Why else would GM have put one on in the first place?

With a car 70% of the braking is done with the front brakes. You'll need to check to see which end of the master cylinder is set for that task. Some are the front res and others are the rear. If the res. are different sizes, the bigger of the 2 is usually the front res. Then you'll need a valve from a 4 wheel drum car with dual inlets lines. A 62 valve should work, shouldn't be much different in weight from a regular Pontiac but one from a 62 station wagon would be as close as you could get without finding one on a hearse.

A valve from a disc/drum set-up won't work because it take more fluid to operate a calipier then a wheel cylinder.

There are aftermarket valves that are adjustable and are around $100. Makes power braking fun too.

[Donnie]

Thats what I thought too but being that I am more of a Mopar man I just took his word.
The line I have going to the front is the bigger of the two but again it seems like it is getting very little pressure out of it.

I forgot to mention that for whatever reason the brake pedel is not coming back up on it's own.
Would it need a return spring? Most all Mopars do.

[Riff Raff]

Unsure on the return spring, but don't all cars have one? Look at the pedal arm and see if there are holes for a spring.

You could have a bad master cylinder, but you won't know til you get a working valve.

[STODD]

With conventional brakes, ALL domestic makes have the same requirement for brakes. There is no difference in operation from make to make. All, again, conventional brake systems work the same.

The master should return the pedal on it's own. The only reason your Mopars have return springs is to assist the pedal for comfort and stress relief on the master itself. The thing to check in your master is the pushrod. It sounds as if it is too short. Remember, you changed your master from one system to another(single to dual reservoir). The dual system will have a longer throw master cylinder being that it is a two chamber design.

Once you dial in the pushrod, then figure out your brake proportioning. You can try out a million prop valves or just make it easy on yourself by buying two adjustable units, install one on each brake system(front and rear) and fool around with them until you find your sweet spot for your brakes. Not only will this give you the brakes you like but it will make you a brake expert and future problems/repairs will be easy fixin' for you.