ok.. so i have a question i kinda already asked in another post.. but im doing my brake conversion... and i was wondering if i could use my stock proportioning valve with my new brake booster and dual master cyl. some one told me that 69 mustangs with drums did not have a prop. valve. so i took a pic. so if any one can tell me what this is and if i can use it or do i need to replace it. .... its the thing to the right

 

Looks to me that this is a distribution block, not a proportionning valve ... could be wrong though

And if your car was a drum set up, which is my understanding, I believe you need to change this block

 

That brass item is the distribution block. Proportioning valves were used on disc brake systems only. Under most conditions, keeping it should be OK.
Jim

 

You are referring to a distribution block in your photo. A proportioning valve will let you adjust brake bias between the front discs and the rear drums. Yes, you will still use the distribution block which appears to have the brake failure switch on it.The proportioning valve is connected between the m/c and the distribution block.
Wayne

 

do i have to use the distribution block if my new proportioning valve has the hook for the brake failure switch on it?

 

You got apples, oranges and bananas.
If you have disc brakes, you need a proportioning valve. It is located on the brake line that goes to the rear of the car on ALL cars, not between the master cylinder and the distribution block. If you do not have disc brakes, you do not need a proportioning valve.
The brake system failure switch is part of the distribution block. You WILL have a switch on both drum and disc installations with a dual master cylinder system. The block is required to separate the brake lines going to both of the front brakes and the single line going to the rear.
Jim