Proportioning valve location

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ValiantOne

ValiantOne

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I am planning on installing a Wilwood single prop valve in my car to balance the disc front upgde vs. The rear drums.

Planning on using:
http://www.summitracing.com/parts/wil-260-8419/overview/

Can I mount this before the stock distribution block? I'd like to have It mounted on the drivers inner fender well, where it is accessible and more protected than mounting down on the frame rail like I see some folks do.

Found the same question in the post linked below asked as a response but never answered.

http://www.forabodiesonly.com/mopar/showthread.php?t=144116&highlight=Proportioning+valve+location

Thanks

CE
 
A two-port valve needs to be the last item in the line on the way to the rear end.
It doesn't matter where you physically install it, so long as it remains bleedable, and the outlet goes to the rear. In theory you could even mount it at the back of the car.

If you have a dual M/C and your distribution block has a safety lite in it, and you put this valve ahead of it, the light will go on every time that you lean on the pedal.
If you do not have a dual M/C, then you do not have this pressure-differential valve. But the new valve still has to be last in line.
Willwood makes a nice combination valve that mounts up high, near or on, the M/C.
 
AJ/FormS said:
A two-port valve needs to be the last item in the line on the way to the rear end.
It doesn't matter where you physically install it, so long as it remains bleedable, and the outlet goes to the rear.
Click to expand...

Hrrrm. So between the master cylinder and the dist block is no good eh? What becomes the problem in that scenario?

Gracias

CE
 
It will shuttle the brake pressure differential switch and turn on the warning lamp.
 
Unless you put some 295s or bigger back there.heehee. That's what I did ; 295s, 10x 2.5,downsized wheel cylinders,and no proportioning valve at all. Shazzam! I have the 11s and was prepared to swap them on, but found so much stopping power with the current system, they're still on the shelf.
 
Better than what we found on my son's 'Cuda last week.... someone previously had used a single MC distribution block and rear prop valve......That combines the front and rear MC halves into 1 system, and then pressure relieves the whole system with the prop valve!#-o

That will be addressed after the initial break-in while setting in the garage....

For the OP:
- Make sure the front brakes are fully bled especially at the MC, and so that you are not being fooled.
- When you put that prop valve in the rear system, it can be a bit touchy and take a number of tries to get it set right so put it in a place where you can easily get to it. Especially if you have a large front to rear mismatch in braking power. The fender well area is a great spot; just plumb in some extra line IMO, and keep it below the MC.
- Be aware that the setting of the prop valve will produce good balance around one range of brake pedal pressures. For example, if you reduce the rears too much at light pedal pressures, the fronts will tend to lock under heavy pedal pressures; not good in the wet. If the front to rear mismatch is too much, you'll never get the balance good over a range of pedal pressures with a prop valve.

At that point, some remedial work is needed, like smaller or narrower rear drums, or better, yet, smaller rear wheel cylinders like AJ used, or use front brake pads with a higher coefficient of friction. Getting the brake balance close to begin with is the best solution. I don't use these prop valves anymore if I can help it, for this very reason.
 
I think 1968 block on drum cars was a "pressure imbalance switch", 1967 or 1966 not. If you reduce the rear pressure (via prop valve) before the block, the imbalance switch will always be actuated.

Even when correctly plumbed, it is tricky to re-center the imbalance switch. Also, insure it isn't rusted in place (like most) so it does its job, though that is why most are "centered".
 
ValiantOne said:
I am planning on installing a Wilwood single prop valve in my car to balance the disc front upgde vs. The rear drums.

Planning on using:
http://www.summitracing.com/parts/wil-260-8419/overview/

Can I mount this before the stock distribution block? I'd like to have It mounted on the drivers inner fender well, where it is accessible and more protected than mounting down on the frame rail like I see some folks do.

Found the same question in the post linked below asked as a response but never answered.

http://www.forabodiesonly.com/mopar/showthread.php?t=144116&highlight=Proportioning+valve+location

Thanks

CE
Click to expand...


Here is a pic
 

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I know its an older thread, but.
I put wilwoods on the front of the 66 dart with the HDK front end. I want to leave the original distribution block in place because of the lines, so, with a dual master cylinder, and line lock, I think the routing is as follows.

#1. Rears.
Master cylinder rear out to proportioning valve rear in. proportioning valve rear out, to distribution block. distribution block rear to the T to the rear wheels.

#2. fronts.
Master cylinder front out to proportioning valve front in. One line out of proportioning valve front out (the other port is blocked) to the line lock. Line lock out to distribution block. Two lines out of distribution block to the front wheels.
Sound correct??
Thanks
 
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