Brake Proportioning valve

[tetomas]

I am upgrading the rear brakes on my 80 elcamino, going with the LS rear discs. I am going to use an adjustable prop. valve for the rear. Now the question: other than working the brake warning light in the dash is there any need in keeping the factory combination valve? I am running all new brake tubing and now would be an ideal time to delete it if it is not needed.

 

[bill]

I dont see a reason to keep the OEM prop valve. Not sure it would work as well with the new set up anyhow.

 

[jlcustomz]

Most people either get a disc/disc prop valve or remove some of the internals before adding an adjustable valve.
May try a search here, has been discussion of that, don't remember whose build threads.

 

[84GP455]

The post to reference is called "LS1 Brake" using just an adjustable prop valve is not going to work. You can't remove the prop valve all together, you need something to build up pressure or you wont get the fluid to the rear brakes. You need a 50/50 prop valve or like he said a disc/disc prop valve to replace the current one in order to get the pressure all the way to the rear. I tried the adjustable prop valve first and there was no pressure going to the rear at all. I got the 50/50 or disc/disc prop valve and that did the job. There is a way to drill out the orifice of the factory prop valve to let more fluid flow to the back but I didn't know for sure what size drill bit etc...etc....so I just bought the correct prop valve. Good Luck!