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Adjustable Proportioning Valve?

  • Thread starter Thread starter wickedmach1
  • Start date Start date Feb 23, 2004
W

wickedmach1

New Member
Apr 8, 2003
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Austin, TX
Feb 23, 2004
#1
  • Feb 23, 2004
  • #1
Any good reason to use an adjustable proportioning valve on my 70 Mach with front disc and rear drums? Should I stay with the stock distribution block until down the road when I will upgrade to rear disc. How does the adjustable work anyway? It has one entering port and one exiting port. Would I need two valves to run the front and rear? Anyone have pics of their setup? Where is the best place to mount the adjustable valves in the engine bay?
 

TurboDoctor

Founding Member
Jan 27, 2002
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San Marcos, Texas(Austin)
Feb 23, 2004
#2
  • Feb 23, 2004
  • #2
I would stay with the stock set up until you get ready to swap for four wheel disks. Some people add an adjustable vavle for personal preferance but you dont really need to.
 

mdjay

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Dec 9, 2003
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Feb 23, 2004
#3
  • Feb 23, 2004
  • #3
Turbo's right. Since your rears are adjustable, you don't really need it at this point...
 
7

70Machwon

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Feb 12, 2004
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Bay Area, CA
Feb 23, 2004
#4
  • Feb 23, 2004
  • #4
I got one in my car, havn't touched it, i only have it since it came with the kit.

It looks like it could be fun to mess with (ie full rear, lockem up and swing around ) oh the possibilities, except i'm sure thats not the smartest thing to do
 

mfp4073

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Mar 14, 2001
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Hells Ditch, FL
Feb 24, 2004
#5
  • Feb 24, 2004
  • #5
Ok, consider this...once upon a time your distibution valve was disigned for a specific car. The car you have now has different tires and weight distribution. The proportioning valve willl allow you to tune your car such that under full braking that both front and rear will lock up the same time. This is a point that is individual to each car based on many things.
 

pabear89

Active Member
Apr 15, 2003
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High in the Hills of So Ca with the Voices in My H
Feb 27, 2004
#6
  • Feb 27, 2004
  • #6
wickedmach1 said:
Any good reason to use an adjustable proportioning valve on my 70 Mach with front disc and rear drums? Should I stay with the stock distribution block until down the road when I will upgrade to rear disc. How does the adjustable work anyway? It has one entering port and one exiting port. Would I need two valves to run the front and rear? Anyone have pics of their setup? Where is the best place to mount the adjustable valves in the engine bay?
Click to expand...

Add the valve when you change the rear to disc, in line to the rear only.
inner fender below the master is a good spot.
The valve will allow you to adjust the brake pressure to the rear disc's so they will have enough power to stop without locking.
that will keep your tail end from trying to pass you in a hard stop.

PB
 

LanceMach

Founding Member
Oct 1, 2002
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SF Bay Area
Feb 27, 2004
#7
  • Feb 27, 2004
  • #7
If you have a problem with the rear wheels locking up during braking you should consider adding it. I wouldn't adjust the rears to correct any problem - they should always be adjusted properly, not loosened up to compensate for an imbalance (just my opinion).

The valve would go in the line that runs to the rear brakes (after the dist block). One side should be marked "In" and that's where the line from the dist block goes.

Chances are you won't need one 99.9% of the time. Even for people who drive like maniacs, the brakes are rarely pushed hard enough to make one necessary. However, in an emergency braking situation (or on road courses), you want the brakes working as efficiently as possible and that means having them balanced so they share the load.

You could check them by finding a nice stretch of road and clamping down on the brakes as hard as you can (making sure nobody is behind you first!). If the rears lock up first, you may want to consider adding the valve. If you do add one, be sure to test the balance every couple months to make sure it's still in balance.
 
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