Just feeling out an idea I had (I'm sure someone else has thought of it before but I didn't see anything).

So my rear brakes were converted to disks, and they just don't stop as well as they should. Tried the stiffer spring, and it helped, but still did not get it to where it should be. I'd like to keep the stock look with the old combination valve and a functioning pressure switch. Would it be possible to disable the prop valve for the rear somehow, then put one of the small adjustable prop valves downstream in the rear brake line? I'm not exactly sure how I'd disable the prop valve, maybe just sealing the hole in the cap and sealing the threads somehow with removing the little plunger would do it, or perhaps installing a rigid piece of pipe in place of the spring...

So is this idea sane? Would certainly be a lot less work to keep all the lines intact and cut/flare the rear line after the combination valve than it would be to replace the combination valve entirely.

 

Why not buy the proper prop valve for a disc/disc car?

 

Because they are exceedingly expensive/difficult to find at this point. If you know a source for them I'd be happy to hear it .

 

I have 2 used ones for sale. Both from disk brake rear cars

$60 each, shipped. If you are interested PM me

 

when i put the '02 disc rear end in my car, i took the spring out of mine and screwed the cap back on.. then i added an adjustable valve in the rear line to dial it in. now that all 4 corners have the "LS1" brakes and the valve is dialed in, it stops on a dime..

 

Take note that the only OE valve that will fit your 91 is the second-design 1LE valve. More info in the 10-Bolt FAQ.

JamesC