Proportioning valve question for disc brake conversion

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LittleSlantSwinger

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Ok so im gonna do a front disc brake conversion pretty soon on my 72' swinger and the thing i dont understand very well cause i dont know much about them is the proportioning valve. So my question is do i hook up the proportioning valve to the rear brake line from the master cylinder when the car is disc/drum only my first conversion so im learning lol.
 
Correct. Prop valve goes to the rear brakes.

Edit....Assuming you mean adjustable prop valve
Yes adjustable proportioning valve comes with the kit i bought dont know much about those valves so thought i would ask on the forum. thanks appreciate it bud!
 
These pictures may help you.

DSCN1047.JPG


DSCN1003.JPG


DSCN1024.JPG
 
Drum brakes benefit from a proportioning- disc brakes do not.
Sorry to disagree. I installed rear disc on my 8.25 from a 97 jeep grand cherokee and added adjustable prop valve. Still need to get proportioning correct with fronts locking just before rears. Best way to do this is in a large, empty and wet parking lot.
 
These pictures may help you
The photos are showing the stock setup, the proportioning valve is integrated into the distro block / brake warning light block.

Earlier years 67 till that went with single piston 72-73??? Was set up that the MC lines went to the distro / brake warning light block. The the rear line went out to the proportioning valve then to the rear end.

IMHO you would want the proportioning valve after the distro block IF it has a brake warning light in it. Other wise you will be feeding one side of the brake warning system with higher pressure then the other and the light will come on at every brake.
 
Drum brakes benefit from a proportioning- disc brakes do not.
Also sorry to disagree, but when I bought a disc conversion kit for my 69 Cuda from Stainless Steel Brakes several years ago, the kit included an adjustable proportioning valve that had to be installed. They recommended on the frame rail right behind the distribution block as seen in the top picture of post #4.
 
Helps me get a decent picture in my head of how im gonna kinda do it. Also photos you have confused me a bit because i saw a couple videos showing lines going into the proportioning valve and then it goes into the stock distribution block, i believe its called that. didnt see both in your picture so curious on what is with that.
What he's showing you is the correct Chrysler disc brake proportioning valve, mounted in the correct stock location. You need nothing else when using that. The valves these other guys are talking about adding into the rear line are aftermarket pieces that were not installed from the factory. If you use the factory piece, like @Oldmanmopar showed you, you do not need the valve in the rear line, because it IS the proportioning valve AND distribution block in one unit. I just got done putting a dual reservoir master cylinder and disc brake proportioning valve on my Valiant getting ready to install front disc brakes. Using the factory stuff made it very simple. Either way will work.
 
Is the Chrysler original proportioning valve ajustable?
It seems to me that my rear brakes lock before my front disks.
 
The photos are showing the stock setup, the proportioning valve is integrated into the distro block / brake warning light block.

Earlier years 67 till that went with single piston 72-73??? Was set up that the MC lines went to the distro / brake warning light block. The the rear line went out to the proportioning valve then to the rear end.

IMHO you would want the proportioning valve after the distro block IF it has a brake warning light in it. Other wise you will be feeding one side of the brake warning system with higher pressure then the other and the light will come on at every brake.
You are talking about 67- 69 cars. the 70 -73 a body cars use this valve and it has the pressure failure light switch in the valve you can see where the wire plugs onto it in this picture.

Here is a link for the correct valve it is also used on the a-bodies. I have a bunch of these valves and I took them all from 70-73 a-bodies

MD2271 - 1970-71 Mopar B / E-Body With Front Disc Braked Combination Valve

DSCN1047.JPG
 
Are you sure you have a proportioning valve and not a distribution block? If you have a proportioning valve they are rebuildable. Here is where to get the kit

1970 - 1976 Mopar Combination Brake Valve Seal Kit | Muscle Car Research LLC

I don't know exactly, but my braking system is totally stock.
I think I have the same proportioning valve than the one in picture posted by Oldmanmopar.
Usage status after 51 years of loyal service
valve.jpg


I preciously keep the two links for the brand new valve and the seal kit. Thanks a lot


François
 
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Chrysler spent millions of dollars to develop their braking systems so why not take advantage of that?
My 69 Barracuda used the complete manual disc/drum setup from a 75 Dart and it worked flawlessly. The plan on my 64 Belvedere is to do the same thing. And for anyone that might disagree a former automotive brake engineer and founder of one of the custom aftermarket brake systems companies agrees with this approach.
 
Drum brakes benefit from a proportioning- disc brakes do not.
I don't know exactly, but my braking system is totally stock.
I think I have the same proportioning valve than the one in picture posted by Oldmanmopar.
Usage status after 51 years of loyal service
View attachment 1715931481

I preciously keep the two links for the brand new valve and the seal kit. Thanks a lot


François
The picture that french demon posted is what mine is like everyone just confused me again but is the proportioning valve going on mine or can i leave it out yall confused me again lol.
 
Is the Chrysler original proportioning valve ajustable?
It seems to me that my rear brakes lock before my front disks.
No. It is preset correctly already. No need for adjustment. Millions were produced with zero adjustment ever needed.
 
You are talking about 67- 69 cars. the 70 -73 a body cars use this valve and it has the pressure failure light switch in the valve you can see where the wire plugs onto it in this picture.

Here is a link for the correct valve it is also used on the a-bodies. I have a bunch of these valves and I took them all from 70-73 a-bodies

MD2271 - 1970-71 Mopar B / E-Body With Front Disc Braked Combination Valve

View attachment 1715931388
The valve you have pictured is the same one I just put on my Valiant with a manual dual reservoir disc brake master cylinder. Although I still have drums all the way around for now, it still stops just fine. I wanted to go ahead and get everything on, since I am getting ready to put the discs on the front. Steve, it always amazes me the level of workmanship yall put into everything. That looks better than new.
 
The picture that french demon posted is what mine is like everyone just confused me again but is the proportioning valve going on mine or can i leave it out yall confused me again lol.
If you are going to disc brakes, you MUST use a proportioning valve, whether it's like the factory one @Oldmanmopar showed you, OR the aftermarket one you add in the rear line. PERIOD. what's confusing about that?
 
If you are going to disc brakes, you MUST use a proportioning valve, whether it's like the factory one @Oldmanmopar showed you, OR the aftermarket one you add in the rear line. PERIOD. what's confusing about that?
like i said in the first post at the start of this thread im still learning. This is probably the biggest thing ive done on my dart besides replacing all old drum brake components in the rear. So my bad if i sound dumb haha.
 
like i said in the first post at the start of this thread im still learning. This is probably the biggest thing ive done on my dart besides replacing all old drum brake components in the rear. So my bad if i sound dumb haha.
You don't sound dumb at all, you sound smart because you're asking questions. I'm just trying to answer accurately so you will know the difference.
 
like i said in the first post at the start of this thread im still learning. This is probably the biggest thing ive done on my dart besides replacing all old drum brake components in the rear. So my bad if i sound dumb haha.
You don't sound dumb at all, you sound smart because you're asking questions. I'm just trying to answer accurately so you will know the difference.
Well i thank you for understanding. For some reason this valve thing has been screwing with me. But i wanna sum it all up now, so i need to install the adjustable proportioning valve above the stock combination block and it needs to be attached to the rear brake line do i have that correct? Also do you think i can go to the auto parts store and just buy some pre-flared and ready to use brake lines? If not then im gonna have to go get a flaring tool and do it myself.
 
Well i thank you for understanding. For some reason this valve thing has been screwing with me. But i wanna sum it all up now, so i need to install the adjustable proportioning valve above the stock combination block and it needs to be attached to the rear brake line do i have that correct? Also do you think i can go to the auto parts store and just buy some pre-flared and ready to use brake lines? If not then im gonna have to go get a flaring tool and do it myself.
No. If you decide to use the aftermarket proportioning valve, all you need to do is plumb it into the line TO the rear brakes. If the master cylinder is a dual reservoir and has a separate line that goes only to the rear brakes, yeah I guess you can plumb it at the master cylinder, but I've never done them like that.
 
No. If you decide to use the aftermarket proportioning valve, all you need to do is plumb it into the line TO the rear brakes. If the master cylinder is a dual reservoir and has a separate line that goes only to the rear brakes, yeah I guess you can plumb it at the master cylinder, but I've never done them like that.
Yes it is a dual reservoir, saw two videos of someone just hooking it into the rear brake line in between the master and the stock combination valve. So i think im gonna do it that way.
 
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