For you guys who've converted to 1LE front brakes on '89 and up cars with the factory rear PBR brakes - do you need a different proportioning valve?

 

I'm not exactly answering your question; however, I converted to both the 1LE fronts and PBR rears. I use the 1LE proportioning valve along with what would be an OE master on an 89+ car. The link I provided elsewhere on the 1LE conversion also has info on PBR's (and what proportioning valve and master are required) that you may find interesting.

JamesC

 

I have the same question.

I have a 91 GTA with factory PBR rear brakes and I'm thinking of installing 1LE front brakes. I believe its the same proportioning valve as I have right now.

JamesC, could you post a link?

Thx.

 

From what I have found in a search and in my parts catalog a 91-92 J65(front and rear disc) cars used the same P/V as an 1LE car.

Seems like 89-90 is a lot harder to figure out.

 

I emailed Spohn. They said my prop valve would be fine.

 

It seems the main issue with P/Vs is the threads. Makes me wonder if there are any thread issues with the flex lines.

 

I have a 91 GTA with factory PBR rear brakes and I'm thinking of installing 1LE front brakes. I believe its the same proportioning valve as I have right now.

JamesC, could you post a link?

The following link is the original how-to:

http://web.archive.org/web/200605221.../1LEbrake.html

The flex lines aren't an issue.

JamesC

 

The main issue is the thread count on the M/C, P/V and the short hard lines that connect them. The hard lines from the P/V to flex lines have the same thread count from 82-92?

 

By flex lines, I'm talking about the line from hardline to caliper.

JamesC

 

Lets get on the same page. Listed in order starting at the M/C.

1. M/C
2. Short hardlines.
3. P/V
4. Hardlines to the flex(rubber, soft)lines.
5. Flex lines
6. Calipers.

Is the thread count the same where 4 and 5 connect the same from 82-92?

Or is it just the thread count between 1, 2 ,3 and 4 the issue between the years?

 

I upgraded my 85 to 1LE. Because of thread count, I used the first design proportioning valve. It was a simple bolt-up to existing lines,(2 & 4). Since 82-83 had some SAE pieces, I'd guess 84+ are the same (5 & 6).

 

I'm more concerned about the 4 & 5 connection.

 

I've never heard of anyone having issues there--I didn't.

JamesC

 

Brining this thread back from the dead instead of starting a new one. Does anyone know for sure that the 1le, and 89-92 j65 cars use the same proportioning valve? I did a c4HD conversion on my car a few years ago, and braking has seemed to be sub par, and since this is basically the same as a 1LE setup I wanted to make sure I have the correct prop valve.
The car in question is 89 Iroc with J65.

 

I keep getting mixed answers

According to this thread they are the same
https://www.thirdgen.org/forums/brak...-answered.html

 

Aside from the first and second design which has to do with thread pitch, they're the same.

1st design: M1.0 tube nut threads (early 1989 applications).
2nd design: M1.5 tube nut threads (late 1989 through 92).

JamesC

 

That's the answer I was hoping for thanks james