Front disc upgrade: good spot for proportioning valve?

[Flanders 46]

I'm currently installing the chocostang front disc-brake package (although I'd imagine this is similar for any front disc conversion) with the K/H 67 Shelby style calipers .  No power brakes, manual trans.

Aside from being slightly annoyed that my new stainless OEM-sized hoses don't fit in the new Master Cylinder (I'm on the hunt for some adapters as the threaded holes in the MC are much smaller than the hose fittings), I could use some advice on where to put the proportioning valve.

The valve is supposed to go between the distribution block and the rear brakes (somewhere in the line that goes to the rear).  It's pretty tight around the distribution block, and bending the rear line while it's in the car seems like a pain in the arse.  

Where have folks put the proportioning valve?  Or is there a replacement distribution block I should get instead that has the proportioning valve built into it?  It would be nice to reuse my existing front stainless lines...so hopefully I'm not delusional.

[Rsanter 152]

Where you put it does not matter as long as it is somewhere in that line.

you can put it in the back between the hard line and the hose. You could also install it inside the car like the racers do, that way you can adjust it as you are driving or you can mount it anywhere else that is easy

 

bob

[Flanders 46]

Thanks -- just trying to find an 'easy' spot to mount it.  I wasn't sure about putting it under the car (or near the rear where the soft hose connects to the hard line) as then it's exposed to the crud that gets kicked up when I drive (if that even matters).

[Cigarwilki 1]

Hello Flanders, 

I don't know what year your car is but it occurred to me that it might interest you to set it up like a 69 model. My 69 sport roof has factory front discs and drum rear brakes. The valve is on a bracket that's attached to the metering block and the assembly is mounted on the engine bay wall right next to the master cylinder. I'm not sure if the exact parts will work on yours. Just thought it might be a good talking point to use a ford set up from a different year. I pulled a pic from WCCC for you. 

[six_sigma 12]

Hey Flanders, this is how mine was set up and I used Chock's front disc package too.

[Flanders 46]

six_sigma: thanks for that pic.  Mine's a bit more cramped since I have no power booster :D but I do have a question for your set up --

you have the proportioning valve between the MC and the distribution block (rear brake input port on the top).  The instructions I see all over keep saying to put the valve after the 'output' port of the distribution block (which is the port on the bottom).

Does it matter if I put the proportioning valve "before" or "after" the distribution block?

 

Cigarwilki: thanks for the suggestion.  I was really hoping to avoid buying another part :D 

[Rsanter 152]

The proper place for the prop valve is after the dist block.

the only thing that can be effected if it is put before is the brake warning light switch. 

While having it before or after the system will function just fine, it can make the setup/balance of the brake warning switch more touchy.

if you do not have a brake warning switch then it doesn't matter.

the other thing is that most of the dist blocks I come across the little slider for the brake warning switch is siezed in which case it won't matter as it won't trip

 

bob

[Flanders 46]

Thanks bob for confirming.

For the life of me I can't seem to disconnect the rear brake line from the distribution block anyway (aside from putting a torch in there, which I'm not too keen on doing considering engine, hood and wiring is all present) so for now it looks like I'll be plumbing this in near the rear axle.  I'll run like this for a while until I have nothing better to do and then may get a valve like cigarwilki pointed out.

[six_sigma 12]

My brake warning light didn't work, the P.O. thoughtfully disconnected the switch for me before I bought it. I guess he didn't want to worry me with pesky idiot lights that wouldn't go off. ;-P

[Flanders 46]

ugh.  an hour at the parts store to discover no fittings that work with the OEM drum lines and new Master Cylinder (or I'd have a stack of 3 fittings to get it to work!).  What a pain in the ass, this is turning into quite the headache.  I can't even find a proper fitting to plumb the proportioning valve into the rear of the car (between the hard and soft lines).  I didn't think it would be this difficult!

My best bet now is to completely remove the existing distribution block and existing rear hard line (which is fused to it) and tackle it when it's out of the car.  I'm also need to bend some new lines to connect the MC to the distribution block (can't use nice new stainless lines meant for front drums).  Overall not terribly difficult, but I was not expecting this part of it to take so long.

If I can manage to get the distribution block out of the car, at least I'll make a mount for the proportioning valve so I can put it under the hood.

[Flanders 46]

the saga continues.  that rear line is anchored under the car fairly well (strange new clips that I don't want to try and break) so can't drop it.  I finally disconnected the rear hard line from the distribution block with vice grips and a hammer.  I couldn't believe it when it finally cracked and spun.

On to bending a whole bunch of brake lines since I can't use my new drum lines anymore.

Any chance there are pre-fabbed lines that would work with the new MC?

[six_sigma 12]

I seem to remember the Chockostang kit I had coming with new small lines for the MC and proportioning valve. I can tell you right now after buying a new ring kit for my distribution block that shuttle that sits under the brake warning light switch would not come out for love or money. In the end, I had to buy the factory distribution and proportioning valve that Cigarwilki showed you. I hope you had better luck than I did.

[Flanders 46]

Yes the chocostang kit came with some lines, however the fittings aren't the correct threads so I need to use adapters on the 3 connections in the distribution block and one of the connections at the MC.   I'll make up some new lines with proper fittings, as I want my engine bay to look really clean -- at least not to draw attention to it. (it's really too bad the lines that came in the kit don't have proper fittings on it to begin with).

[six_sigma 12]

19 minutes ago, Flanders said:

Yes the chocostang kit came with some lines, however the fittings aren't the correct threads so I need to use adapters on the 3 connections in the distribution block and one of the connections at the MC.   I'll make up some new lines with proper fittings, as I want my engine bay to look really clean -- at least not to draw attention to it. (it's really too bad the lines that came in the kit don't have proper fittings on it to begin with).

Yeah, that does suck. if you want clean, I think I remember seeing a pic of an installation where the prop valve was mounted on its side under the MC so the adjusting know was just visible at the side. You had to know to look for it.

[Cigarwilki 1]

Flanders, I bought some new steel brake line with "the wrong" thread and size connector for some after market brake cylinders. I ended up cutting my existing brake like and patching the new line straight to it via a compression coupling. Picture attached. This one is steel. I used brass. 

[Cigarwilki 1]

You can buy generic steel brake line at any parts store with connectors. Probably the wrong ones for stock application and right ones for non-stock newer stuff. Cut the line with a tube cutter. Use whichever fitting you can find that is correct and then  with the compression coupling you can insert it anywhere in your system with confidence it won't leak. 

[Flanders 46]

I'm finally back at this job again...amazing how crap gets in the way of Mustang work :)

I'm still having difficulties getting the proportioning valve into the system.  Basically, I can't seem to find a proper adapter to go between the rear hard brake line (OEM) and the proportioning valve.  

 

As Cigarwilki pointed out, the OEM 1969/70 proportioning valve should do the trick nicely because it will fit my existing OEM hard line fittings (not that I'm keen on trying to remove my existing distribution block!).  BUT, how does this proportioning valve work?  Is it compatible with the 67 K/H Shelby-style front rotors (ie. chocostang, and even SSBC front disc conversion kits), or will it only work with the 1969/70 front disc brakes?  

 

Any help would be mucho appreciated.  I've visited too many shops and turned away each time because I can't get proper brake line adapters!  That rear hard line fitting size is apparently odd!

[Mike65 475]

On 6/29/2017 at 10:11 PM, Cigarwilki said:

Hello Flanders, 

I don't know what year your car is but it occurred to me that it might interest you to set it up like a 69 model. My 69 sport roof has factory front discs and drum rear brakes. The valve is on a bracket that's attached to the metering block and the assembly is mounted on the engine bay wall right next to the master cylinder. I'm not sure if the exact parts will work on yours. Just thought it might be a good talking point to use a ford set up from a different year. I pulled a pic from WCCC for you. 

When I added power disc brakes to my 69 Coupe I se it up like the factory system using the above pictured proportioning valve/distribution block.

 

[Mike65 475]

Ooops, double post.

[Flanders 46]

Thanks Mike -- what front discs did you use for your conversion?

[Flanders 46]

ok, I think I've got it sorted out (Dan@Chocostang has been very supportive).  The ultimate problem was the fittings.  I've got two sizes, below:

The top one has all the right threads, but the seat for the inverted flare on the brake line looked too big.  I thought it should match the fitting seat size on the bottom one (which is clearly smaller).  The brake line will sit in the top fitting, it just doesn't have as much overlap.  Chocostang says it's ok to use the top fitting, so it looks like I can make progress again.  Hopefully nothing leaks :)

[Mike65 475]

On 9/11/2017 at 3:45 PM, Flanders said:

Thanks Mike -- what front discs did you use for your conversion?

Flanders, I purchased the kit in the attached link from OTR, but when I received the parts they were in boxs from CSRP.

http://opentrackerracing.com/product/ford-kelsey-hayes-type-4-piston-caliper-power-disc-brake-kit-v8-with-manual-transmission-1967-1969-copy/