Connecting an adjustable proportioning valve to stock distribution block

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Madison, WI
My Car
1971 Mach 1 w/408C stroker
Like the title says, I am trying to connect an adjustable proportioning valve directly into the stock distribution block. I just finished installing disk brakes all around, but keeping the stock distribution block. I guess I should have tried the system to see if it worked, but I thought I will add an adjustable valve to add customization.

The long story short, is that I have spent a lot of hours searching in the web, and I have purchased a bunch of fittings, but still I am not finding the ideal solution. The adjustable proportioning valve has 1/8" NPT female connectios.

The problem is that the rear brake connection in the stock distribution block is for 3/16" tubing inverted flare (IF) with a 7/16-24 nut. Basically, and this is the only way I found, is to have a 7/16-24 IFM adapter to AN-3 hose, then an AN-3 hose adapter to 1/8" NPT. This seemed to work, in theory, until I realized today that the 7/16 IFM adapter is for 1/4" tubing instead of 3/16". I have not tried under pressure, but I assume it will leak. Thoughts?

I am out of ideas. I think having the adjustable valve connected directly to the stock distribution block looks very clean and elegant, but I can't find the adapter I need. I basically need an adapter with a male flare for a 3/16" tube and 7/16-24 thread, to 1/8" NPT male. If I can't achieve this with one adapter, I am okay with a maximum of two adapters in series.

Any thoughts or ideas? Keep in mind that the space where the stock distribution block is very limited, and I can't fit a tube in between. Otherwise, I will have to leave without an adjustable valve (short term solution), or relocate the adjustable valve somewhere else. Where have you typically installed the adjustable proportioning valve?

 
My thoughts:

What type of brakes was your distribution block made for? If it's the one in "H" shape, it's as you said...just a distribution block. If it's the dog-leg shaped one (used on disc brakes) it has a metering valve built in and may not be compatible with an adjustable proportioning valve.

I do not think your adapter made for 1/4" tube will seal properly.

I think you should be able to find a single fitting to do what you want but I can't offer a specific site that has it. I like to find a source for what I'm looking for, get an idea of any specific nomenclature used, then use a general google search using "images" to quickly home in on what I'm looking for. I've found that oreillys has a lot of different size flare nuts and adapters but their search doesn't always find them....a google search using your search terms follow by (less the quotes) "site:eek:reillyauto.com" or wherever you're searching...I've found lots of parts this way that otherwise did not show up using the vendor's search engine.

 
My thoughts:

What type of brakes was your distribution block made for? If it's the one in "H" shape, it's as you said...just a distribution block. If it's the dog-leg shaped one (used on disc brakes) it has a metering valve built in and may not be compatible with an adjustable proportioning valve.

I do not think your adapter made for 1/4" tube will seal properly.

I think you should be able to find a single fitting to do what you want but I can't offer a specific site that has it. I like to find a source for what I'm looking for, get an idea of any specific nomenclature used, then use a general google search using "images" to quickly home in on what I'm looking for. I've found that oreillys has a lot of different size flare nuts and adapters but their search doesn't always find them....a google search using your search terms follow by (less the quotes) "site:eek:reillyauto.com" or wherever you're searching...I've found lots of parts this way that otherwise did not show up using the vendor's search engine.
Mine is the D0OA-2B328-D combination valve for disk brakes. So, you can't connect an adjustable valve to it, do you know why?

In regards to fittings I have spent hours searching in many different ways, including O'Reillys, Dorman, Earls and many others, with no luck.

 
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I thought the Parking brake pedal has a switch under the dash and activates the small round "BRAKE" dummy light on the dash?

 
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I thought the Parking brake pedal has a switch under the dash and activates the small round "BRAKE" dummy light on the dash?
Sorry for the confusion, what I meant to say with emergency brake light is the light that turns on when you lose brake line pressure in either the front or rear circuits. This is separate to the e-brake.

Basically, the SSBC has a light switch incorporated for applications where the rear brake light is activated by line pressure. In ours, the rear brake light switch is by the brake pedal. The stock proportioning block in our cars have a light switch that activates if the pressure between the rear and front brake lines is different, which would be likely an indication of a problem with the brakes or fluid leakage.

 
I understand what you are saying. I had the "idiot light" come on one day after my booster failed and was only getting manual brakes, which was close to no brakes. But why would SSBC stipulate the part for our model car if the wiring isnt correct? The are a pretty good supplier of ford brake system parts...and the harness attachment looks identical to the attachment on the OEM block...which by the way has a tendency to fail at that plastic part that blows when you are pumping the air outta the lines. arrrrg. Did you speak to SSBC about their design? Or an alternate piece they might have?

 
TM, yeah i see your point on the wiring. So if you use the SSBC block you can easily dial in the pressure to balance the front/back...but then the real "idiot light" won't light up if your line pressure fails. Well, as I said above, my experience was that it only lights up after the brake system has already failed, so what are you losing really? And you would have properly modulated brakes that can be installed immediately. best of luck on it. reminds me of when i swapped out my gas tank and sending unit. new units do not light up the "get gas NOW" light so you have to pay attention...but they work better than the one I was pulling out of the tank it terms of getting fuel to the pump!

 
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I understand what you are saying. I had the "idiot light" come on one day after my booster failed and was only getting manual brakes, which was close to no brakes. But why would SSBC stipulate the part for our model car if the wiring isnt correct? The are a pretty good supplier of ford brake system parts...and the harness attachment looks identical to the attachment on the OEM block...which by the way has a tendency to fail at that plastic part that blows when you are pumping the air outta the lines. arrrrg. Did you speak to SSBC about their design? Or an alternate piece they might have?
I have not talked to them, but if you read the description, it says, "Includes wiring pigtail for rear brake light switch." I have read similar in other descriptions and threads.

Good point about the idiot light, which is more idiotic than what I thought. Sometime back I lost most of the braking due to a leak in the rear and the light did not turn on until most of the fluid has drained a few hours later.

 
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In any case, ideally, I would like to use the original distribution/differential valve block with an adjustable valve added. Has anyone added an adjustable valve? and where/how was it installed?

 
If I may throw in a bone here. When I added SSBC manual front disc brakes, the kit was supplied with an adjustable rear brake valve that is totally separate from the front. My car was manual drums. The rear outlets are plugged off on the distribution block and the low pressure brake light switch is left unplugged so I have no idiot light for brakes. When I upgraded further to a power booster recently, I did have to make some changes and needed brake line adapters. You will need to go to a parts store that specializes brake lines and the sort. Your average chain store likely won't have them. You will have no trouble getting the proper fittings if you go to the right place. Later, I am going to change to a one piece combination block if I can find one so I get my warning light back.

Hope that helps,

Geoff.

Edit: I may have a picture that shows what I have. If I do I'll repost.

 
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This is the best picture I have right now. It was taken way before I redid the engine bay and added the power booster. You can see the adjustable valve to the left of the original. I'll try to get another taken that may be more helpful.

 
My thoughts:

What type of brakes was your distribution block made for? If it's the one in "H" shape, it's as you said...just a distribution block. If it's the dog-leg shaped one (used on disc brakes) it has a metering valve built in and may not be compatible with an adjustable proportioning valve.

I do not think your adapter made for 1/4" tube will seal properly.

I think you should be able to find a single fitting to do what you want but I can't offer a specific site that has it. I like to find a source for what I'm looking for, get an idea of any specific nomenclature used, then use a general google search using "images" to quickly home in on what I'm looking for. I've found that oreillys has a lot of different size flare nuts and adapters but their search doesn't always find them....a google search using your search terms follow by (less the quotes) "site:eek:reillyauto.com" or wherever you're searching...I've found lots of parts this way that otherwise did not show up using the vendor's search engine.
Mine is the D0OA-2B328-D combination valve for disk brakes. So, you can't connect an adjustable valve to it, do you know why?

In regards to fittings I have spent hours searching in many different ways, including O'Reillys, Dorman, Earls and many others, with no luck.
Tony,

The distribution block for disc brakes has a built in metering valve that requires 125 psi within the distribution block to open the valve allowing pressure to the front brakes. This is, in essence, a proportioning valve that is tuned to what Ford believed was appropriate. The addition of a manually adjustable prop valve may very well work with the stock combo valve, but you will be working with 2 independent valves to accomplish the same thing. I can't say with certainty that it will or wont work, just mentioning the potential conflict between these two parts.

Regards,

BT

 
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