CamaroX84

I'm almost done converting my car to 1LE B4C brakes. I have a disc brake rear from a 92 Camaro. Which masters and prop. valves will work with the 1LE setup? Thanks in advance.

Eightyninef

is that 1LE front brakes too, or just the J65 rears?

ebmiller88

iTrader: (7)

M/C part number 18014286, same as the J50 disc/drum cars.

Prop valve part number 14089496-1st design, M1.0 tube threads
10136840-2nd design, M1.5 tube threads
10136840-90-92 cars, all

Check your brake line threads for the one you need.


If this doesn't answer your question, do a search under "1LE" and you'll find it in there. Also, you could search for my postings, ebmiller88. I listed all the M/C and prop valve part numbers and their applications a couple months ago.

Let me know if you need more help.


AndyZ28 is a master with this stuff, too:hail:

Eightyninef

>>>10136840-2nd design, M1.5 tube threads
>>>10136840-90-92 cars, all <<<

that part # has been long discontinued. It is dead. I don't know why people keep referring to that number.

It has been supseeded by another number 10164112.

The strange thing is this #10164112 is for ALL front disk brakes. 1LE and regular front disk brakes use this combo valve !!

how could that be? the same combo valve for all small disks and big disks. (this is assuming you have J65 rear disk)

maybe GM figured out the right pressure releif spring for the rears, and let the fronts be ?????

Larry

ANDYZ28

You guys sure have saved me a lot of typing. ThanX!

ANDYZ28

CamaroX84

I am using both the front and rear 1LE brakes. Which years proportioning valves are those part numbers that would work? Thanks.

ebmiller88

iTrader: (7)

Thanks Larry, my mistake. I got those numbers from Daniel Burke's page since I had it up. Guess I should have just checked my own post.

X84, it depends on what brake line threads you have as to which valve to use. Since your car is an 84 I think, you will probably need the first design, 14089496, but you should measure to find out for sure.

CamaroX84

So are the proportioning valves throughout the years any different inside? Or is it just the fittings? Thanks again.

ANDYZ28

I am currently researching this subject. And as I am sure "ebmiller88" knows. I will post the exact correct answer.

Won't I "ebmiller"?

Eightyninef

of course they are different. It's not a prop valve #1, it's a combination valve.

The basic function is it limits the rear brake presure. once the presure hits a certain predetermined point, the spring opens up, and thus no more pressure is applied to the rear brakes. This prevents the rear from locking up and hopping down the highway.

rear Drum brakes need more pressure than rear disk, therefore the spring is heavier for drum brakes.

apparently GM didn't get the combo valve right until 1990. that's why in 1990 there are only 2.

1989 there are 6 valves (partly because the thread pitch change)
I think in 1990 there were more BC4 and 1LE cars, so they finally got it right.

ebmiller88

iTrader: (7)

I posted all the part numbers for the combo valves and master cylinders a while back can't find them anywhere on the site. They're buried in some obscure post womewhere. I'll list them again.

As for the combo valves being different inside, I have no clue, but I'll stick with Larry's post and with Andy's seat of the pants testing.

BMmonteSS

I'm doing a similar swap on my monte carlo. Going form stock rear drums to the small disk setup 10.5 inch. The question i have is will my stock m/c work? I have heard that the drum side of it has a check valve in it somewhere that has to be removed. I also heard that drums take around 300 psi while disk take bout 2000 psi so would it be the oposit of the last post. I have no idea of the acuracy of this info thats why i'm asking you all for help. Will i be able to use the proportioning valve listed earlyer or is there a different one for the smaller rear disk.