I just put in a 9 bolt posi rear into my 92 camaro rs. I went from rear drum to disc and bought a disc prop valve, I think. I bought it from a guy on here. I tried to see if it would fit where my existing one is located, but there are either some parts missing or I need another line. CHeck out my pics and tell me if this is a disc prop valve or not. If not I need one if anyone has one for sale.

 

That's not a thirdgen proportioning valve. Compare it to the one in the following pic:

JamesC

 

I think it is an early style before GM went to aluminum valves in the late 80s, I saw one like that on a '84 or so car in the scrap yard. You can't tell disc or drum just by looking at them, the differences are internal.

In any case, replace it as it's iron, old, and likely very dirty inside.

Ed

 

Not like the OE in my 85, and i've never seen one like it. I wonder if it's part of the 82-84 weirdness?

JamesC

 

Possibly, and they're ugly as well. I modified one off a MCSS for a rear disc setup and it looked just like that.

Ed

 

I am not sure what it is off too. I am trying to get my money back on this one, because it obviously doesn't work for my application. I don't know what goes into the front of it. It looks like another line, but I think a plug with a screw bleeder is suppose to go there. I bought this from CAMFIRE. Has anyone dealt with him before? Do any of you have a disc brake prop valve for sale?

 

The threads may be SAE instead of metric (as the later cars were).

JamesC

 

its a prop valve from a 82-83 Car. possibly 84 as well but i'm not sure on that. I do know that my 83 has one identical to it, I pulled one from a 82 disc/disc car for my disc swap and it is identical as well. as mentioned before there is no way to tell if it is from a disc car by looking at it, and yes, those older steel prop valves are SAE fittings. I had to make custom lines going from the prop valve to the MC because I'm running a LS1 master which is metric.

 

thanks for all your help. The guy I bought it off of is taking it back and sending me a newer style one.

 

I need to rebump this thread. Just reading through the forums and came across this.

My 83 had one that looks like the original post. That was on my drum car. I swapped in a LS1 rear and bought a replacement prop valve.
The one I bought was from a board members claimed 83 Camaro. It looked exactly like my drum one.
We had a problem installing it as none of the original lines were fitting it. The one I bought did not come with any fittings or lines. So we decided to take apart the old and new one to see if we could transfer parts from one to the other so I wouldn't have to change lines. The bottom unscrews off, but it took major force to do it. There's a spring and a pin if I remember exactly. I think they were identical, but I'll have to ask my friend as I don't remember.
I ended up using the replacement "disc" prop valve. I had to cut my original fittings and crimp on replacements. Funny thing is, it turned out to be metric. Which doesn't make sense as I read 82-83 are supposed to be SAE.
The brake pedal feels weird, but I'm not sure exactly how it runs as I haven't driven it much. Still working on it.

Any ideas what I have?

 

the one on my 83 camaro looks like that but it has sum sort of nipple on the back...anyone know wat it is?...

 

This is the type of valve I have on '85 Z28 with drum brakes. Appeared to look original to the car. Fittings to MC and brake lines were metric. Plug for spring and valve are standard. I did a disc conversion and modded the valve with the stiffer spring. Fixed my brake problems.

 

My 84 se had this iron prop valve with disk axle I swapped it all too my 87

 

It's been reported that some of the old-style iron valves were converted to metric before the newer style, so you were probably a bit lucky.

JamesC

 

JamesC,
Noticed the strut tower brace in your pic. can you tell me where you got it ? All i can find is one for TPI cars. Thanks

 

Check Summit or Jeg's for QA1 5227.

JamesC

 

Got it , Thanks for quick reply

 

BTW, you might consider installing after market strut mounts (eliminating the rubber donuts of the OE) to more fully realize the benefit of the STB.

JamesC