[Mike Davis]

Looking for a new Proportioning valve for a 1980 TA with 4 wheel disc.
All I see is the Brass type online.
Anyone have a recommendations?

[burd]

What’s the part. number?

[78Macho]

Mike-

I had my original valve rebuilt. If you don't have your original unit you might try to buy a used one and have it rebuilt. I found in my research the new units will work but don't look like the OEM.

If you have further questions, email me.

glasic74@hotmail.com

Jim

[burd]

Hunt an nOS one down.

[77 Canamman]

The original GM part number was 1257189. If you want the assembly line style, you will be very lucky to find one nOS or have to have an original used rebuilt by White Post. Even GM was selling the all brass ones as OEM replacements..

[Skip Fix]

I want to think the one I took off my 81 was all brass.

[78w72]

original one on my low mile 1981 turbo is not brass.

personally, unless you are planning a 100% 3's matching correct resto i would just buy the repro brass one for ~$60 & paint it black if you dont like the brass look. or try & find a good used one that works or can be rebuilt. locating a NOS 4 whl disc prop valve might take awhile & will not be cheap.

[burd]

I thought 1979 up was that brass one there. You can find them, this stuff isn’t rare.
I have an extra nOS for my 78. Coming to the parts this late, yes, your going to have to look. Try the usual suspects,

[78w72]

not brass on my 81 low mile T/A. & cant say ive ever seen a brass one on the many 79-81 cars ive owned. might be a issue where they used them at certain assembly plants or only when they ran out of the iron ones?

[burd]

Back to orig question, why are you replacing, is it bad?
Flush it, plug the holes, bead blast it, paint it, I even went with Dot 5, just flush it out and re use.
A nOS one is prob over 150$

[Mike Davis]

Originally Posted by burd

Back to orig question, why are you replacing, is it bad?
Flush it, plug the holes, bead blast it, paint it, I even went with Dot 5, just flush it out and re use.
A nOS one is prob over 150$

Before I purchased the car it was left out in the rain with the hood off. Someone stole the Master Cyl cover and it was full of water. Proportioning valve is rusty and the lines are twisted off.
Replacing entire brake system right now including MC, lines, calipers, rotors etc might as well put a new valve on while it's all apart.

[Skip Fix]

So Mike just saw a 80 W72?

[78w72]

Originally Posted by Skip Fix

So Mike just saw a 80 W72?

pretty sure W72 was an option for the NA 301...

[Mike Davis]

Originally Posted by Skip Fix

So Mike just saw a 80 W72?

Yes, 1980 WS6 W72 SE non T-top car. Bought it last summer and restoring it (minus the 455 thats going in) for a Dad/Daughter car to take to cruise nights and car shows.

[Aus78Formula]

Fair to say non-brass NOS in discs is rare. If most have never seen one, and those hunting specifically for years have never seen one, that possibly qualifies. Hard enough finding a used original and then risking the condition of it.

[burd]

I recall seeing the brass ones on 4 wheel disc cars.

[Skip Fix]

I got you, I always assumed a W72 was a TA 6.6 motor. I put a mild 400 in the 81 SE T top car I got for the kids to drive to high school. Now they are grown I have a 455 slated for it! I pulled off my prop valve and T'd the fronts and have an adjustable in the rear now.

[Scarebird]

Skip has the right idea here - a lot of the repops are set up for 1971 Chevelles. A good adjustable valve works quite well and of course can be tuned for vehicle specifics and conditions.



Summit's house brand works very well:

https://www.summitracing.com/parts/sum-g3905

I am sure Jegs, Speedway and the like offer equal value.

[Mike Davis]

Thanks Skip and Scare. I may go that route. I am trying to make this thing look like a 100% stock TA under the hood. Keeping the 4.9L on the scoop etc. I let my 10yo daughter pick how she wanted to do it. She chose the sleeper route.
Here is the current valve that was on the car.

[Skip Fix]

Man there is either a lot of rust or undercoating on that sucker! My 81 had way more undercoating on it than I have seen almost like dirt mixed deep into it! Mine still has the lockup TH350. A factory type convertor was super tight, I have Continental make a 13" lock up one but never used a lockup on it.