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View Full Version : Proportioning valve before or after residual valve?



DarkoNova
05-28-2008, 07:25 PM
I finally got everything I need to put my disc brakes on and now I'm stuck. The instructions just say get the residual valve as close to the master cylinder as possible, but it doesn't say if it goes before or after the proportioning valve.

So my question is, which should be closer to the master cylinder? The proportioning valve? Or the residual valve?

Master cylinder -> residual valve -> proportioning valve -> rear brake line

OR

Master cylinder -> proportioning valve -> residual valve -> rear brake line

:confused:

Matt

gearheads78
05-28-2008, 07:33 PM
Are you running drum rear brakes? If not skip the residual valve all together.

DarkoNova
05-28-2008, 08:46 PM
Yeah, I'm running rear drums. Soon I'll have 4 wheel discs, but for now I'm sticking with drums in the rear.

Matt

amx2334
05-29-2008, 09:35 AM
Residual valves on factory drum cars were in the port on the master.I would put it right after the master before the prop. valve.

DarkoNova
05-29-2008, 11:15 AM
Ok I just called Touring Classics and he said not to even run a residual valve. I told him I was running rear drums and he said to first try it with just the proportioning valve. :hmm:

I guess that would work, but I just don't see the rear brakes doing much of anything if there's no residual pressure. :confused:

Matt

6'9"Witha69
05-29-2008, 11:18 AM
Don't worry about RP on a drum car as the stock setup is already equipped for that. Never mind that Drums require less RP than Disc cars (10 v. 2 pounds) so even if you did put an RP valve on it now for the drums you would have to replace it later when you converted to discs.

DarkoNova
05-29-2008, 01:17 PM
Alright, well I'm still stuck. The guy at NAPA said the line size for the rear brakes should be 3/16", so I got 2 feet of 3/16". I get home and find that the rear line size looks even bigger. What size is it? 1/4"?

The proportioning valve I have has 1/8" NPT threads, so hopefully I can find adapters to fit.

My other problem is I have no way to bleed the friggin master cylinder. I thought they'd at least send me plugs or bleeder tubes or something, because I'm pretty sure I got those with my last master cylinder, but I got nothing. If I can't find any plugs local, could I just put it in a vice, fill the reservoirs and pump it? I figure I could catch the fluid in a pan and just do that for like 5 minutes and it should be good. Maybe?

Matt

6'9"Witha69
05-30-2008, 08:26 AM
No. The MC will take in a little air on the backstroke. If you have any extra fittong for the MC use some extra hard line and go for it. You only need single flares to do this for bleeding purposes.

DarkoNova
05-31-2008, 11:19 AM
Thanks, I found a kit at Kragen for $5 for bleeding master cylinders. I finally got everything on and I went to bleed it and found the passenger rear bleeder valve was broken off. So after replacing both rear wheel cylinders (driver's side was just a precaution), I finally was able to bleed the system.

I've done everything except install the new master cylinder. It's a universal one and you have to measure and cut it. The instructions say 69 Camaros are usually around 5", but when I measured I only had 3.5" of room. Anyway the pedal is nice and firm and doesn't go down too far, and I'm positive there's no air left in the system so I'm happy with it.

Thanks for all the help. I've gotta get some 1/4" spacers, but once I get those, I'll get some pics of the new brakes/wheels. :)

Matt