I installed a pair o 44's last weekend with caddy calipers in the rear. I need to install a residual valve and also installing a different MC.

Does it make a difference where the valve is located in the line for the rear?

Close to the MC or near the axle?

I'm guessing id doesn't make a difference but thought I'd check.

the ones i'v seen are built in the MC

Why are you putting residual valves on a brake system with rear disc brakes? The purpose of a residual valve is to hold front brake pressure back until the rear wheel cylinders (on rear drum brakes) have taken up clearance. Right?:smokin:

You need to run A RS valve in the back if you have disks. If you dont thay will chatter. Vehichles with disks front and rear factory have RS valves front and rear in the master cylinder allready.

The mc I'm using is from a 68-76 vette (4 wheel disk brakes) with a 1 1/8" bore. But it doesn't have any residual valve built into it.

dawhipp - the residual valve keeps some pressure in the line (2lb for disks) to keep the pads just on the surface of the disk so that you don't have to use allot of peddle stroke for the brakes to work. At least that is my understanding of it.

According to the info from Wilwood you are supposed to locate the residual valve as close to the mc as possible.

OK first I admit I was having a "senior moment" and confused residual valve with metering valve:emb2: The RV belongs on the rear line (duh). But "normal" four wheel caliper systems do NOT need them. The 2PSI residual valves are only needed if you're running Wilwoods or AirHearts with mechanical retraction pistons. Or a race car/hot rod with a low mounted MC. Common production seal retraction calipers don't need them (they're not on my '86 Vette either). The 6-25PSI residual valves for Disc/Drums(usually in the combination valve)is used to overcome the spring retraction of the springs on the rear shoes.

This site should help: www.mpbrakes.com/mpfaqvalvinging.htm

Now as far as this chattering thing is concerned... never heard of using a residual valve for that. Chattering is usually caused by rotor runout or hard-spotting. I can see how a residual valve would cause chatter, not stop it. Can you point to an (factory) application that uses residual valves front and rear? :D or is that:flipoff2:

Thanks for the link. The MP site has allot of good info.
Had I know about it before I tore into this project it would have saved me some $$ on the residual valve that I don't appear to need.