Proportioning Valve

[67barracuda]

Looking for a picture of the  Proportioning Valve with labeling of the line used with a disk brake swap on a body. disk front, drums rear, 73-up

[ski]

From an old post.

A= master cylinder marked F for front brakes, be careful it's actually the rear m/c reservoir. 
B= right front brake.
C= left front brake.
D= rear brakes.  They'll split downstream.
E= Master cylinder marked R for rear brakes, again be careful this is the front or smaller m/c reservoir.

Pic is a stock 73 Valiant valve.  Front disc, rear drum.

[67barracuda]

Ok, I couldn't hold pressure with the brake system. I think it was sucking air, so I removed line "D" rear brake line according to the chat above and put a plug in its place. I now hold pressure in the system. So I must have a problem with the rear brake line. Sound right? Or can I not plug the prop valve to isolate a line?

[ski]

Sounds right.  You could cap off each rear brake line at the slave cylinder one at a time to find out which line is bad.  If it still won't hold pressure then go back to the block where the rear brake line splits and plug both outlets.  If it still won't hold pressure the problem is probably the single line between the prop. valve and junction block.  Are you losing fluid?

[PureGTS]

Uh, news flash...  the master cylinder does the proportioning. The "block" pictured is just a glorified "tee" with a shuttle valve in it that is used to turn on the brake warning light to tell you of a braking problem. It severs no other purpose, so you don't have to change this when you convert to discs from manual brakes. Take one apart sometime and you'll find out there is really nothing in there and is identical to the other "blocks" of various braking systems.

[abqdart]

I just ordered the summit brand distribution/prop valve......