I have rear discs off a granada, the same as the lincoln setup, and have only pulled the car in and out of the garage a few times to go to an from different shops (body, muffler...) I have noticed that the rear brakes seem to be dragging. I think it may be something with my distribution block. I have a stock granada distribution block from when I did my front disc conversion. It cam from a drum brake rear car. Is there something special I have to do to make the brakes work properly without dragging. It is not severe, I can still push the car with little effort. The only reason I can tell is that the coating on the rear rotors is scratched more than the front.

I planned on driving the car for a little while before adding an adjustable proportioning valve. Do I need one now? Thanks

 

You will probably notice a world of difference with a proportioning valve installed.

 

With four wheel disc, I don't think you need a proportioning valve. That valve was used to delay the rear drums to give the front discs a chance to grab.
Jim

 

The most important step that many forget when doing this type of conversion is the residual pressure valve. If your brakes are dragging most likely your porportioning valve has nothing to do with it. 66GTKFB was absolutely right about what he said. It's true that's what a porportioning valve does but, if your car came with rear drums then, it's 99% possible that it came with a residual pressure valve. Cars with rear drums have this and what it does is it holds 10psi of residual pressure to the rear brakes, so that when they are engaged their ready to go to work. if you convert to disc you don't need this valve.

 

If your rear brakes lock up before the front then you do need a proportioning valve to keep that from happening, regardless of any other issues with a residual valve.

My advice is to eighty-six everything, run the front lines to an open tee out to the front wheels and the rear line straight from the MC to an adjustable proportioning valve then back to the rear discs. By trial and error, keep adjusting the proportioning valve so that they come on as strong as possible without locking up before the fronts.

 

So are you saying that I can fully bypass the distribution block and run the rear brakes directly from the master cylinder? I won't need a proportioning valve at all?

 

The propper distribution block also has a brake failure switch that will light up the brake failure indicator. There should be two lines from the master cylinder to the distribution block and then one to the rear brakes and two to the front brakes. An early 67 disc brake type should work. Ford used different fittings to keep the assembly line workers from hooking them up wrong. That's the only hang up.
Jim

 

OK, if I keep the distribution block I have now and run the front brakes throught it (basically using it only as a t) and then bypass the rear brake port completely will the brake failure light work or do you need both lines connected for it to operate normally? For the rear brakes I would add a portioning valve where the distribuion block normally would be (master cylinder to port block to rear brakes). Does this sound like it would work?

 

What master cylinder are you using? If you have one for disk/drum, it may be best to switch to one from a disk/disk setup, such as the Versailles, then use a stock Versailles distribution block (mainly if you want a brake failure switch), although that may or may not be necessary- I think youll know pretty quick when you have a brake failure.

 

If you don't need a prop valve for rear disk brake cars, then why do they sell them?

Proportioning Valve - Street Rod
Street Rod - Brass 5 Port Valve Front Disc - Rear Disc
Brass
$99.00