Residual valve

[1toolguy]

While redoing the Cordoba's brakes I discovered that the distribution block was bad and replaced it with an adjustable proportioning valve plumbed to the rear brakes. I just recently learned that by doing this my rear brakes may not be functioning properly because there is no residual valve in the system. Residual valves are actually pretty inexpensive so I'm willing to install one but I have two questions:
1) How much pressure should the valve I get hold?
2) Does it matter where it's mounted?

 

[AMX364]

Residual valve is located in the master cylinder. It is behind the brake line connection ie. at the seat of the brake line. If you use a self tapping screw into the center of the opening and use pliers you can remove the seat and valve and spring located behind it.

 

[bm02tj]

If you keep your brakes adjusted up you will not notice it is missing
as you will not be able to pump the brakes up like in the old days
when they needed to be adjusted

 

[mopar 3 B]

The residual valve has nothing to due with brake adjustment. It's only function is to restrict the flow of brake fluid in the system.

 

[Photon440]

More than restricting the flow, it retains pressure in the system.

http://www.mbmbrakeboosters.com/ind...tent&view=category&layout=blog&id=8&Itemid=16