Brake companant question, brass metering block?

[Rileys68Camaro]

I have a brass colored block that my lines from my master cylinder connect to, and then from there to the brakes.



What is it? Do I need it? It has a electrical fitting that I assume is for a brake warning light or some such.

I have the SSBC front disc kit on my 68 Camaro.

If it's safe, I'd like to get rid of that brass block to clean up the engine bay and make for one less thing to worry about.

[Milow68]

Brass colored???? In Wisconsin usually looks rusty? LOL. I think your talkin the proportion valve? You will need that!!!!! The electrical wire is for your brake warning light. It mounts down on the inside the frame? Has two brakes lines coming in from the master cylinder and two going to the front brakes and one line going to the back and then the electrical connection.
If that isn't it I did have a high mounted proportioning valve on a 70 Cutlass I had back in the day (about a dozen years ago). Don't remember much I only had it for about a month before parting it out.
Hope this helps!
Brad

[Rileys68Camaro]

Doesn't the proportioning valve have the adjustment knob on it?

I don't know what this thing is, never seen one on a car before. Maybe it is a preportioning block.

[andrewb70]

Its a non adjustable factory style prop valve. You need it.

Andrew

[1976SR71]

If you are upgrading to rear discs from drums you need to bypass it with the rear line and add an adjustable unit....Factory drum brake proportioning valves have a pressure holding feature...That will kill rear discs!!!

[Rileys68Camaro]

I'm going to replace the whole system with a C5 kit, but for now need to make this work.

Just wanted to make sure before I added fluid to the lines.

So, do I need the adjustable valve right now?

Thanks all!

[68BNUT]

If you changed from drums to discs on the rear you cant use the factory metering block it wont pass enough pressure to allow your rear discs to work properly. I just did the drum to disc conversion on my 68 and I used the Inline tube proportioning valve that they sell looks just like the factory one. And it has the conection for your brake warning light

[Rileys68Camaro]

Rears are factory drums.

Just trying to get some brakes going, need a new master too.

[68BNUT]

are you keeping the rears drums??

[Rileys68Camaro]

for now. Just trying to get it on the road as inexpesively as possible for right now. I'm loosing motovation after 6 years and all the troubles. So I want to enjoy it a bit, and upgrade the other stuff on the weekends.

[68BNUT]

oh man i know how you feel i tried to get by with some old equipment on my conversion I did the fronts and rears at the same time ended up waiting like 2 more weeks just cause I didnt order a new booster and the old one was long shaft new was short shaft

[novaman_68]

I did the drum to disc conversion on my 68 Nova and temporarily used the stock drum/drum factory prop valve. The car stopped fine, the front brakes locked up just before the rears. I always heard the same thing about the car not stopping but that isn't true, it stopped fine. I wouldn't recommend running that drum prop valve forever but it WILL work well enough to get the car on the road.

[fuzzyonion]

67-69 GM F, X, G, & A bodies... The original brass block does not have any proportioning or metering valves in it. They were separate pieces until early 70's. You can use it to distribute the lines and work the warning light, and add a rear adjustable valve.
That brass block was the same for disc and drum cars until they started using a combination valve.

distributor and switch assembly, 67-69+, disc/drum/drum(5 ports)



valve, front brake pressure metering, 67-69+, front disc only (2 ports, 1in-1out)(note black rubber button on left side of pic)


valve, rear brake proportioning 67-69+, front disc w/ A/C (2 ports, 1in-1out)


Later cars,
valve, combination
disc/disc (5 ports)


disc/drum (5 ports)

(note button on front)

If this applies to you I hope it helps.

There were lots of different GM part #s to these, but they were all similar in appearence.

[Rileys68Camaro]

The bottom two pictures look like mine.

Here's another question, with a rear adjustable valve and a disc/drum master cylinder, do I need that? The mechanics got a bunch of poorly bent, not pinched, but ugly lines running and they just look like to much.

I'm wonderering because looking at the included parts in the kit, it doesn't show that brass block. The kit came with a new disc/drum master cylinder. Stainless Steel Brakes Company part #A123 for the kit.

Thanks!

[Rileys68Camaro]

So maybe I do need a new pushrod, oh well they're cheap.

I will have the brakes checked by a good shop though once I get on the road!

[fuzzyonion]

With a rear adjustable valve you shouldn't be also running a combination valve. One or the other only, unless you remove the proportioning section from the combo valve.


If it had looked like the splitter in the first pic (it is also brass) you could run an adjustable with it, since it hasn't any internal balance valving.

The A123 kit comes with an adjustable to use with the OE splitter, so someone must have added the combo valve, got rid of the original splitter, and hopefully not used the adjustable.

The proportioning valve reduces pressure to the rear brakes during hard stops.

Pushrod?

[Rileys68Camaro]

So can I rid myself of the combo valve and get a splitter? What would I need for a splitter?

Yes, they installed the rear proportioning valve too.

Going to get pics, be right back.

[Rileys68Camaro]

You can see the brass valve, and the black thing that looks oily is the adjustable proportioning valve. Yes, the master cylinder I had leaked and ate the paint and generally made a mess.

This is the mess I'm trying to clean up. Should I buy new lines or what else can I do to clean it up and make it nicer? Don't really want to cut an flair.

[fuzzyonion]

If it was mine, using the A123 kit, I would get rid of the adjustable and run the rear line straight into the back of the combo. Then buy or make a bracket to bolt the combo valve to, and buy all prebent conversion lines for the master and front brakes.

Whilt the lines were down, I'd tape up all that wiring.

[Rileys68Camaro]

I had bought new lines, but maybe they're wrong.

Working on the wiring too, getting some convoluted tube and trying to figure out where to run it a for clean look.

I'm still trying to decide if I should partially dissasemble the front end and start again from there. Maybe put the wiring between the inner/outer fenders if that's a good idea.