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-   -   propotioning valve ? (https://classracer.com/classforum/showthread.php?t=46545)

js72mav 03-31-2013 10:58 AM

propotioning valve ?
 
Does the adjustable proportioning valve go before or after the line lock solenoid? And why? just trying to understand.... thanks!

Todd Hoven 03-31-2013 03:29 PM

Re: propotioning valve ?
 
I have a question to add to this? On a car with aftermarket racing discs on the front and drums on the back, what line do you install it on? Front or rear

Ed Wright 03-31-2013 03:43 PM

Re: propotioning valve ?
 
Rear, which also answers the previous question.

js72mav 03-31-2013 04:01 PM

Re: propotioning valve ?
 
Now I am even more confused than before. Strange says that in drag cars it is usually in the front and street cars on the rear line.

Todd that is the same set up I have, discs in the front and drums on back.

mike britt 03-31-2013 04:20 PM

Re: propotioning valve ?
 
Put mine on the rear and have the valve all the way open. Should of left it on the shelf.

Dana Fitzpatrick 03-31-2013 04:34 PM

Re: propotioning valve ?
 
I installed Strange discs front and rear on my drag-only car. I was told by Strange and others to put the prop valve on the front brakes due to the small front/larger rear tire combination. Also put it before the line-loc. But I seem to remember Strange saying that if I were to use drum brakes out back, put the prop valve in the rear. The deciding factor might be if you are running skinny tires up front,in which case you may want to limit the braking power to them. If your discs are aftermarket, I would check with the manufacturer.

Todd Hoven 03-31-2013 04:56 PM

Re: propotioning valve ?
 
Same here Jamie. I bought new Strange front brakes and they told me to install it on the front. Willwood says to run it on the rear. My car had Willwoods on the front and it always seemed to have to much front brake bias. Strange also told me to run a 2 pound residual valve for the rear brake line.



Quote:

Originally Posted by js72mav (Post 375911)
Now I am even more confused than before. Strange says that in drag cars it is usually in the front and street cars on the rear line.

Todd that is the same set up I have, discs in the front and drums on back.


gmonde 03-31-2013 05:25 PM

Re: propotioning valve ?
 
something to try before you install the proportioning valve ,, if you have access to pressure gauges for brakes ,put one the front ,one on the back apply pedal pressure and read gauges ,,if its higher on the rear install on the rear ,,higher on the front maybe you don't need one or install on the front ,, my calipers are the same size on front and rear ,I put mine on the rear line gmonde

1720 03-31-2013 05:49 PM

Re: propotioning valve ?
 
Quote:

Originally Posted by mike britt (Post 375915)
Put mine on the rear and have the valve all the way open. Should of left it on the shelf.

Same here! Rear wide open.

Dave Noll 03-31-2013 06:03 PM

Re: propotioning valve ?
 
...

Ed Wright 03-31-2013 06:47 PM

Re: propotioning valve ?
 
If it is a race car, you do not want the rear brakes locking first. Lot more traction on the rear than the skinny fronts.

Todd Hoven 03-31-2013 07:36 PM

Re: propotioning valve ?
 
Quote:

Originally Posted by Ed Wright (Post 375930)
If it is a race car, you do not want the rear brakes locking first. Lot more traction on the rear than the skinny fronts.

I cant imagine being able to lock the rears up before the fronts. It is most likely easier to lock the fronts than the rears due to the weight of the driveline plus the car being under power. . You don't want the front brakes doing all the work either. If you have 4 wheel discs the brakes work evenly.

SPS 03-31-2013 07:45 PM

Re: propotioning valve ?
 
OK.

First, Ed is correct.
The proportioning valve should be for the rear brakes. Can be in the rear line wherever you wish to install it, locationwise.

Reason, again, as Ed says, you definately don't want the rear brakes locking up before the fronts. You will swap ends before you can think about it.

Those of you that have the valve open (off), can possibly be for a couple reasons. One, if foot braking, you won't have enough pressure to hold the rear wheels to leave on the converter. Also, this can be by having different (smaller) rear brakes on the rear.

In all the cars I have and do build, I install the valve. I'd rather see someone have to open it up some than not have it and lock the rear brakes.

Now, I have been a Strange dealer for longer that I'd want to admit, so if there is some misunderstanding of info re installation, I' d like you to send me either a PM or e-mail me at info@smithperformance.com and I'll follow up.

hope this helps.

FJ

js72mav 03-31-2013 08:18 PM

Re: propotioning valve ?
 
Thanks for all the help guys. Here is what I have, I have a 1972 ford maverick with aftermarket discs up front and stock drums on the rear. I have a stock master cylinder and stock proportioning valve / distribution block. I have a lot of drag on the front wildwood brakes. What would you do to correct the problem? I already tried brand new calipers and it is exactly the same. Just trying to learn how all this stuff works together, thanks!

Dave Noll 03-31-2013 08:28 PM

Re: propotioning valve ?
 
...

SPS 04-02-2013 07:58 PM

Re: propotioning valve ?
 
A good possibility of the dragging front brakes is the factory master cylinder having a residual valve built in it.
This is to keep the stock brake pistons in contact with the rotor so little travel (ie pedal movement) is necessary to make them work.

My suggestion would be to replace the master with the mopar style available from Wilwood.

We use and sell lots of them with no problem.

FJ

js72mav 04-02-2013 08:06 PM

Re: propotioning valve ?
 
Thanks, I will replace it. That does make sense. Thanks for your help!!

Ed Wright 04-02-2013 08:32 PM

Re: propotioning valve ?
 
If you have an F body like mine ('93/'02) FJ has a great master cylinder kit with the MOPAR cylinder, mounting plate, firewall brace and instructions for drilling the pedal to correct leverage. Works great.
He offers a lot of great stuff for these cars.

MLP 04-02-2013 09:25 PM

Re: propotioning valve ?
 
Quote:

Originally Posted by Ed Wright (Post 376159)
If you have an F body like mine ('93/'02) FJ has a great master cylinder kit with the MOPAR cylinder, mounting plate, firewall brace and instructions for drilling the pedal to correct leverage. Works great.
He offers a lot of great stuff for these cars.

And PLEASE make sure you have the proper brake rod retention device in place so nothing terrible happens. I know two people that have failed to do so and are lucky they survived.

sst1226 08-18-2013 10:08 PM

Re: propotioning valve ?
 
So I have a question. 69 nova with stock manual disc brake master cylinder 1 1/8" piston and stock proportioning valve, strange 4 piston caliper front brakes up front and getting ready to swap drums out back for 4 piston discs in the rears. Skinnys up front, 14x32s out back.
Will i have to run a proportioning valve to the rear to prevent too much bias/ possibly lock up the rears?
I foot brake the car if that makes any difference, usually leave off the foot brake at 4000rpm.

rallye bob 08-19-2013 05:03 AM

Re: propotioning valve ?
 
Quote:

Originally Posted by 1720 (Post 375923)
same here! Rear wide open.

x3


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