Proportioning valve help

[ItDoRun]

Before I started my current build, I installed a set of LS1 brakes on the front of my car. I didn't use a proportioning valve, but instead used a Wilwood residual valve between the front and rear of the car. After fabricating all new lines for the car, I learned that they make a 1/8-27 NPT and a 1/8-28 NPT thread.

What size is the connection that's leaking?

[JRouche]

Originally Posted by ItDoRun

Before I started my current build, I installed a set of LS1 brakes on the front of my car. I didn't use a proportioning valve, but instead used a Wilwood residual valve between the front and rear of the car. After fabricating all new lines for the car, I learned that they make a 1/8-27 NPT and a 1/8-28 NPT thread.

What size is the connection that's leaking?

Interesting. But I dont think there is a NPT in 1/8-28. The standard is a 27tpi. Not saying there isnt a 28tpi in some pipe threads, just that its not NPT. JR

[akrapovic]

What size is the connection that's leaking?

The 1/8 NPT fitting is leaking on the proportioning valve side.

[GregWeld]

So here's my .03 worth...

IF -- big IF -- you're running big ol fat tires in the rear - I'd leave the Prop valve OUT of the system. It's sole purpose is to reduce pressure to the rears just to the point of having the FRONTS lock up before the rears.... On most builds the fronts are narrow compared to the rears... so they're going to lock up (with brake dive added in etc) before the rears do. I'd only add the prop valve back if, after a test drive and the pads all bedded in etc it was needed.

Can't leak if it ain't there! LOL

I'm serious about leaving it out - if the above fits your build.

[akrapovic]

Well, is 295/35 considered big? I have plans on going to a 335 but not in the near future. I may have to consider eliminating it if my problems persist.

[Vegas69]

I have my proportioning valve dialed all the way out and have no problems with rear brake lock up. I'd leave it in the system just incase. Wilwood uses a special thread sealant on their proportioning valves. It looks almost like a dried red loctite.

[akrapovic]

Todd,

Baer had the same red stuff on theirs. This third one seems to be holding up. I snugged it up took it for a drive and it seems to be ok so far. Maybe I was just being over cautious and didn't properly tighten. Only time will tell I guess.