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Discussion Starter · #1 · (Edited)
Decided to treat my Scarebird front discs with a (rear drum) adjustible proportioning valve and a 10# residual valve. My original plan was to splice them in place of the union I have down by the distribution block. They arrived today and the PV, even though it is an in-line job, is heaver that it looks.

What about this? 1.) with a male-to-male fitting, screw the RV straight into the Master Cylinder port. 2.) with a male-to-male fitting, screw the PV straight into the RV. 3.) Fit the rear brake line into the PV.

Wondering if it would look bad or work bad. Or should I not worry, the brake lines will hold the valves up fine.
 

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You can place it any where on line....

And if you don't want to see it period,you can place it at rear of car where hard line connects soft hose at frame....
Just make sure you install in right direction....:)

edit: just to claify...i was speaking of residual valve...

prop valve keep closer to master...also at a easy accessable location....
 

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Decided to treat my Scarebird front discs with a (rear drum) adjustible proportioning valve and a 10# residual valve. My original plan was to splice them in place of the union I have down by the distribution block. They arrived today and the PV, even though it is an in-line job, is heaver that it looks.

What about this? 1.) with a male-to-male fitting, screw the RV straight into the Master Cylinder port. 2.) with a male-to-male fitting, screw the PV straight into the RV. 3.) Fit the rear brake line into the PV.

Wondering if it would look bad or work bad. Or should I not worry, the brake lines will hold the valves up fine.
If you have a flaring tool capable of double flares, and some tubing benders, why not bend a 5D (radius of bend meaning 5Xdiameter of tubing)90 degree bend and set your fittings on spare tubing.Then attach the valves. If you have coils in the line between the MC and the Distribution block, you will have the necessary shock absorption capabilities for the hydraulic system. In essence, hang the valves where you can access them under the hood if needed; if you don't mind seeing them under the MC and booster .
 

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Discussion Starter · #4 ·
Okay I'm fixin to install my proportioning and residual valves. This will entail removing a 12" tube from the master. Any tips?

Before I reinstall it can I save some bleeding effort by pre-filling the tube and valves with fluid?
 

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No not really.
 

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Discussion Starter · #6 ·
Does this look ok? the red one is the residual valve and the seat looks wrong. Hole too small, flat on top. Though the port is bigger it is still supposed to take a 3/16 IF tube, just like the one on the right. Wonder if it will, without leaking?
 

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Puttster - ignore the shape down inside the residual valve. That's just the shape of the fitting they use internally. Verify this on yours, but almost all aftermarket RVs use 1/8 NPT threads. Assuming this is true for yours also, then you need to use a IFF to 1/8" NPT Male adapter. The IFF end is whatever your brake line has or will have on it for an inverted female flare fitting - usually 3/8-24 IIF for 3/16" line, but could be another size if you're using a fitting that used to go to the MC.

The RV uses 1/8 NPT so that you can adapt directly to another part without having to use line in-between, or any size line with generic fittings. The inverted seat you see in the RV is not used for sealing. HTH

David
 

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The residual valve should have had the fittings installed.
 

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Discussion Starter · #9 · (Edited)
This end of the residual valve had black 1/2-20 nut. They wanted me to put the nut over a 3/16 tube and flare it. I wanted to use my existing flared tube. So I bought a fitting, 1/2-20 with a 3/8-24 on the other end (pic). That's when I noticed the difference internally. The one I bought is much more cone-shaped than the black one. Think it will work out?
 

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Discussion Starter · #10 · (Edited)
Update: I installed the adjustible prop valve and the resid valve and got no leaks. When tightened down all the way the PV produced a loud braking screech! from the fronts. With the PV backed out all the way braking gave a gliding but okay stop, no noise. Halfway between gave me a visible nose dive on braking and no screech except when braked hard from high speed. Is that about what I am looking for for adjustment?

Also, can I leave the valves up on top (pic), supported only by that green pliable brake line?
 

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Discussion Starter · #11 ·
bump?
 

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Update: I installed the adjustible prop valve and the resid valve and got no leaks. When tightened down all the way the PV produced a loud braking screech! from the fronts. With the PV backed out all the way braking gave a gliding but okay stop, no noise. Halfway between gave me a visible nose dive on braking and no screech except when braked hard from high speed. Is that about what I am looking for for adjustment?

Also, can I leave the valves up on top (pic), supported only by that green pliable brake line?
I don't see why that mounting arraignment won't work, the lines should support the weight of the valve just fine.

I don't understand the screech tho. Are the pads squealing, or are the front brakes locking up?

The PV job is to restrict line pressure to the REAR brakes to help balance the system. The FRONT brakes always have full pressure. Find an empty parking lot or a stretch of road that you can run up to 30MPH or so then hit the brakes hard. Start with the PV wide open and keep doing test runs and closing the PV about a turn each time till the REAR brakes ARE NOT locking up before the fronts.

Holler back if this isn't answering the right questions.
 

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I only read about the stopping.

You DO NOT want a Nose Dive.

You DO want a slight tip forward, but if you want to replace all your components at the same time in the future, the more even the stopping the more even the wear front to rear.

Also, put a big load in the trunk and do your stop test again {couple fat chicks from Houston should work}. You got a lot of crap to bring to the BBQ this year and I dont' want you not being able to stop when you get out of the comfort of the plains and into the wondrous Cascade and Blue Mountain ranges of the Pacific Northwest. :D :D :D


FE
 

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+1, you want maximum braking from the rears, without locking-up before the fronts. You can start testing on a dirt road to see the tracks at lower speeds. If there is no premature rear lockup, re-test on pavement, but dirt is a good test, as it must work right in rain and other slick conditions so you don't spin-out in bad weather. You may need no reduction at all. Every system (car weight, weight distribution, brake pad material and area, cylinder sizes, etc.) is different. Did you test for premature rear lock-up before installing the valve?

David
 
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