1970 disk brake line routing??

[jasonn]

I am switching to disk brakes from drum. Both 1970 spindles and hardware. Original 70 proportioning valves. The old valve has 2 lines in the top. They are from the master cylinder. These 2 are the same as the disc vavle. Both valves have 2 line coming out the bottom. I am guessing these are the same. But my drum valve has the last line coming out the front. The disc valve has a line coming out of the rear. Can anybody tell me what the routing is off of the proportioning valve for a disc brake setup?? I would THINK that I just need to route the one line to the back but I would like to know for sure. thanks much.

 

[jasonn]

Anybody??

 

[ultrastang]

Jasonn,

The flow rates in the brake circuits in front vs. rear are not the same in a drum/drum system vs. a disc/drum system.

Proportioning rates are governed by the combination valve. The one you have is for your stock drum/drum setup. Will it work with a disc/drum setup? Yes. Will it work correctly? NO.

The Granada combination valve is very similar in function (as well as looks) to the valves for a '70 Mustang that came with discs front/drums rear.

You can buy brand new valves through CSRP for less than $40.00
http://www.discbrakeswap.com/combo1-valve-5-web.gif

http://www.discbrakeswap.com/



www.ultrastang.com

 

[jasonn]

I actually have both. The one that was original on the car (drum,drum) and I also pulled the original one that I pulled the disc brakes off of. (disk,drum). So I do have the right one. It is just plumbed a bit different. Like I said, everything looks to be plumbed the same except for one of the lines points towards the front and on the disk,drum one there is a line that comes out and points towards the rear of the car. This is the line I am wondering about.

 

[ultrastang]

I actually have both. The one that was original on the car (drum,drum) and I also pulled the original one that I pulled the disc brakes off of. (disk,drum). So I do have the right one. It is just plumbed a bit different. Like I said, everything looks to be plumbed the same except for one of the lines points towards the front and on the disk,drum one there is a line that comes out and points towards the rear of the car. This is the line I am wondering about.

If there is plenty of brake fluid still trapped inside the used disc/drum valve, and the valve has not dried out, it should be fine to use.

 

[69gmachine]

The top rear facing port goes to the right front.
The bottom rear facing port goes to the back wheels.
The top forward facing port goes to the left front.
The bottom forward facing goes to the front reservoir of the MC.
The top port goes to the rear reservoir of the MC.

Now is the ideal time to install an adjustable proportioning valve in line with the rear wheels near the distribution block. I also removed the plunger so that I would have the maximum range of adjustment with the proportioning valve.

 

[jasonn]

Thanks gmachine!!