Proportioning Valve

Trying to finish up the 4-wheel DB swap on my car.
A little back ground, I am using a 2003 Cobra setup on the front and rear. 99-04 V-6 Master Cylinder.

Option 1) A Disc/Drum proportioning valve off a late 60's Early 70's Fairlane/Torino. Number off of valve D00A 2B328 D X

Option 2) A Drum/Drum proportioning valve off a 70 Mustang Coupe Number off of valve D0 A-2B257

Option 3) Just use a "T" to go from the Master to the front brake lines. Then a short peice of line to make up the difference between the old rear line and the master.

Option 4) The valve from the 99-04 V-6, this would require me finding adapters though and possibly having to modify the lines. (My least favorite out of the options.)

All options except #4 I will be using a Wilwood proportioning valve inline for the rear brakes.

Option 1 seems like a direct bolt in, but not sure how this valve differs from the mustang valve.

Option 2 I have some interest in knowing if it would work would need to drill different hole in the apron to mount it. Looks very simuliar to the first valve, for the fronts a input and two outputs to feed the fronts. One rear in and one out.

Option 3 there would be no way to attach the "T" to the apron. I would also have no internal valve to block the fluid incase of a blown line.
 
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if you don't want to mess up with brake tubes don't use valve from SN95. There are metric fittings. If you decide to cut your rear line, definitely go with manual proportioner, which IMO is the most reliable option. Eg Wildwood prop uses 3/8 x 24 ---< type fittings which are easy to install on stock 3/16 line
 
Trying to finish up the 4-wheel DB swap on my car.
A little back ground, I am using a 2003 Cobra setup on the front and rear. 99-04 V-6 Master Cylinder.

Option 1) A Disc/Drum proportioning valve off a late 60's Early 70's Fairlane/Torino. Number off of valve D00A 2B328 D X

Option 2) A Drum/Drum proportioning valve off a 70 Mustang Coupe Number off of valve D0 A-2B257

Option 3) Just use a "T" to go from the Master to the front brake lines. Then a short peice of line to make up the difference between the old rear line and the master.

Option 4) The valve from the 99-04 V-6, this would require me finding adapters though and possibly having to modify the lines. (My least favorite out of the options.)

All options except #4 I will be using a Wilwood proportioning valve inline for the rear brakes.

Option 1 seems like a direct bolt in, but not sure how this valve differs from the mustang valve.

Option 2 I have some interest in knowing if it would work would need to drill different hole in the apron to mount it. Looks very simuliar to the first valve, for the fronts a input and two outputs to feed the fronts. One rear in and one out.

Option 3 there would be no way to attach the "T" to the apron. I would also have no internal valve to block the fluid incase of a blown line.


i was wondering the same thing. I am thinking of using my original 70 disk/drum valve with adjustable proportioning valve when i install disks front and rear. What did you end up doing?
mike
 
Either option 1 or 2 will work just fine. Just remove the factory restrictor on the rear line. This piece is what makes it a proportioning valve and not just a distribution block. It is not needed if you are installing the adjustable valve and will limit the range of adjustability. They are sized for the weight of the car, type of front and rear brakes, and front to rear weight balance.
 
Either option 1 or 2 will work just fine. Just remove the factory restrictor on the rear line. This piece is what makes it a proportioning valve and not just a distribution block. It is not needed if you are installing the adjustable valve and will limit the range of adjustability. They are sized for the weight of the car, type of front and rear brakes, and front to rear weight balance.

where is the factory restrictor on the rear line? do yo mean the "T" at the rear axle?

thanks
 
option 3.....the T works just fine. The only real reason for the proportion valve is if you are racing and running hard IMO.

The only down side you list is "blowing a line" . Let me ask you this..."how often do you hear of folks blowing a brake line?"

I went thru this on my Chevelle with 4wheel disc. wasted a LOT of time configuring the system because all the retailers "SELL YOU" on the idea you NEED it. LOL...that was a 400 hp car, I didn't race it very often and there was plenty of track to slow it down. Point is I bought into the "sale" and thought I needed it. A good ole boy mechanic pulled me aside and said "son.....don't buy s.... you don't need" LOL:rlaugh: Laughing at the ole man of course not you or the thread.

IF that is something you like, PST...has some good brackets that mount to the frame, and yes they are pretty cool and it is interesting how well they work.
 
Either option 1 or 2 will work just fine. Just remove the factory restrictor on the rear line. This piece is what makes it a proportioning valve and not just a distribution block. It is not needed if you are installing the adjustable valve and will limit the range of adjustability. They are sized for the weight of the car, type of front and rear brakes, and front to rear weight balance.

Thanks for the info. Does the shuttle valve restrict the flow of fluid when it activates the switch for the brake warning light? Or is it just activate the switch?

option 3.....the T works just fine. The only real reason for the proportion valve is if you are racing and running hard IMO.

The only down side you list is "blowing a line" . Let me ask you this..."how often do you hear of folks blowing a brake line?"

I went thru this on my Chevelle with 4wheel disc. wasted a LOT of time configuring the system because all the retailers "SELL YOU" on the idea you NEED it. LOL...that was a 400 hp car, I didn't race it very often and there was plenty of track to slow it down. Point is I bought into the "sale" and thought I needed it. A good ole boy mechanic pulled me aside and said "son.....don't buy s.... you don't need" LOL:rlaugh: Laughing at the ole man of course not you or the thread.

IF that is something you like, PST...has some good brackets that mount to the frame, and yes they are pretty cool and it is interesting how well they work.

Thanks I just want to do this the correct way. Your right you don't hear about the brake lines going out often.
 
Ok, I'm being a little slow.......

I have a cobra set up on my 66 and I used a 94 cobra mc with an inline prop valve on the back brakes.

The prop. valve is wide open and I still can't lock up the rears. My lines are run directly to the mc and this is a manual brake system.

Is there a restricter somewhere in this mc I don't know about?