Brake biasing

[Rickey_Bobby]

I have 13" cobra brakes up front, and stock in the rear of my 99gt.

the biasing, to me, is not good, I can lock up the front easily when the rears are nowhere close to locking. Now I know the rear only stops about 20% of the car, but hey, thats still 20%

is there any way to adjust the brake bias F/R?

I realize adding the cobra rear brakes would "help" but I would like to have them adjustable so i can put them just where I want them with my tire/suspension combo.

Ideas?

 

[Red2000GT]

There are adjustable proportioning(sp?) valves that you can buy but i don't know how it will work with the abs system.

 

[Rickey_Bobby]

My ABS computer died, and I'm too cheap to replace it.
So the valves are prettymuch universal then?

 

[Mustang5L5]

My ABS computer died, and I'm too cheap to replace it.
So the valves are prettymuch universal then?

Well then that's why you are having a problem with bias.

On modern cars equipped with ABS, they really don't even use a proportioning valve anymore. The ABS does the brake bias. If the fronts are about to lock, the ABS tells the computer to send less pressure to them.

To add an aftermarket prop valve would be a brake line plumbing nightmare since you have two individual brake lines to each of the rear brakes. A real PITA to setup using one prop valve

It would be cheaper and easier to just fix the ABS...not to mention safer and more performance orientated. You should fix what's broke, not baid-aid it with some hack-job modification



I have the same brake setup...13" front and stock GT rears. With ABS it's great because you can lay into the brakes as hard as you want and it will stop on a dime.

 

[Rickey_Bobby]

well my thinking was.... Ford dealer wants $500+ for the ABS computer. For $500, I could have one hell of a proportioning valve...

 

[tomustang]

well my thinking was.... Ford dealer wants $500+ for the ABS computer. For $500, I could have one hell of a proportioning valve...

or you can call an ABS module rebuilder and have it rebuilt for half that, you can either call these two and ask them if they do mustang modules

www.modulemaster.com
http://www.autoecu.com/

 

[tomustang]

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[tomustang]

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[Mustang5L5]

well my thinking was.... Ford dealer wants $500+ for the ABS computer. For $500, I could have one hell of a proportioning valve...

Fixing the ABS is a much better solution.



Your problem is not brake bias, but the fact that your front brakes are just much more powerful than the rears. To fox this you would need to reduce pressure to the front brakes...which defeats the entire purpose of why you did a 13" kit to begin with. You start reducing pressure and the next panic stop you have will have you slamming on the brakes and wondering why the car isn't stopping.

Fix the ABS, it will reduce pressure only when you need it