I ordered and put on a Moser 9" rearend that I got from Hawk's, but in order for the axelk setup to work properly i had to change out the stock drum brakes in the rear with disc brakes. Well with that I had to upgrade the proportioning valve. I went to hook it up to the existing brake lines and the threads are completely off, course matching up with fine and vice versa. I wrote Hawk's an email about it incquiring as to what year camaro the proportioning valve went to and they told me probably off a '89-'92, keep in mind the proportioning valve is brand new. At any rate, they said to have a machine shop either make adapters or rethread the existing ones on the valve itself.

What do you all think the best course of action is to do here, esp since i was told it would hook right up and work like a charm?

 

Why not just get another proportioning valve?

 

The new one they sent is the one that goes with this rear disc setup. They sent it with the brakes themselves. Told me I would need it.

 

What rear brakes does it have? The 89-92 12" discs with aluminum PBR calipers? The thread pitch changed mid-year in 1989. Get a proportioning valve for an "early" 1989 car and you should be ok.

The location of the port for the rear brake line changed between 1984 and 1989 too, so you'll probably have to bend your factory line to get it to line up, but the threads should match, at least.

 

exactly, it's the 89-92 set. So you are saying there's a difference between the proportioning valve within the YEAR? Or all 89's had the same thread setup?

 

You need the first design prop valve, P/N 14089496.

Ed

 

In the beginning of 1989 they used the old thread pitch, then changed it in the middle of the year. Ed's part number looks right for the early 1989 unit with the threads you need.

 

So the threads on the proportioning valve with that part num. will have threads that line up with the adapters for the brake lines that are orignially on my car? no mods needed?

 

The threads on that proportioning valve will match the threads on your lines, however the rear brake line will probably need to be bent to line up with the new port location.

 

awesome, is this available through a GM dealer or a special order from a restoo place?

 

Probably from the dealer. Proportioning valves aren't usually available from the aftermarket.

 

Just an update... I ordered the part num. you all said it might be and it's the exact same prop. valve as the other one i got new that came with the rearend. So I guess I'm going to have to get some adapters made if any place even does that

Didn't realize this would become such a hangup.

 

Can you measure the size of the fittings and the thread pitch? What do the flared ends on your lines look like?

 

I'll have to wait until i get back to my shop... I'm away at school right now and won't be back until next Thursday for summer. I'll try and firgure it out then and let you all know. I don't know if the mismatched course and fine threaded line ends between the prop. valve and the lines is bc of the fact that the car is a Sport Coupe and this is coming off a later version camaro??

 

In 82 and 83 SAE threads were used.

From 84 to early 89 everything had the same metric threads, but the body of the proportioning valve itself changed at some point from cast to machined aluminum with the rear port in a different location.

From 89 up threads were still metric, but they were the different pitch.

 

Well then due to the change after 89... that must be why i have course threads on my break lines trying to go into FINE threads on this prop. valve and vice versa for others.

Should I just get adapters to solve this problem?

 

Your car is an 84 though, so presumably so are you brake lines. The early-89 prop valve should have worked.

 

Back at my shop they match it up and the threads on the prop. valve(P/N 14089496), the one i just ordered mathed exactly to the prop. valve i had earlier that was supposed to fit correctly, so there was still mismatched course to fine threads. Go figure...

 

Curiouser and curiouser.

 

yeah this is really weird. why wouldn't all the 3rd gen's be the same? That's such a small minor detail. Wouldn't think they'd change something as insignificant as this.

 

im not sure about 84 being the same as my 88, but i would do this, call a local dealer & ask them the "code" on your 84 prop valve.
the prop valves dont have part #'s on them, but they do have "codes" 88 & earlier ? are "NB" for 4 wheel disc, mid 89 to 92 are "MB", look at your prop valves & see what they have stamped on them, if its "MB" its definately the wrong one for you year, but maybe right for the brakes, not sure on that.
on the "MB" code 2 of the fittings are metric, 2 & 1.5 as i recall, they look like course threads, but nothing ive found fit
this all prolly doesnt directly answer your ?'s, but i hope it helps you solve it
Shawn

 

I think it's going to come down to simply getting adapters to get this prop. valve to fit the brake lines properly.