Wilwood Disc Upgrade - Questions

I am upgrading the CJ5 to Wilwood front disc brakes. A local shop changed the knuckles to CJ7 disc and the discs and rotors are on. That all looks great!

The issue we are having is with the proportioning valve. The Wilwood proportion valve has a different type of fitting than the stock brake lines.

Is there a way to adapt the Wilwood proportioning valve to the oem brake lines? I would like to do that as Wilwood says I need a 10lb Residual Pressure Valve which would go down stream from the proportioning valve on the rear brake line. The other option is new brake lines and the ones I have are stainless and they are nice. I would hate to change them.... costly too!

Is the stock unit that is there a metering block or a proportioning valve? Could I not use the Wilwood valve and just the stock 'valve'? Wilwood said the stock valve might have a Residual Pressure Valve build in... maybe?

Thanks in advance!!!

 

Which Wilwood proportioning valve do you have? There are different fittings, from pipe threads, metric, invert flare, to AN/JIC. All of Wilwoods's proportioning valves that I am familiar with (not a big sampling of what they offer) do not have residual pressure valves built in.

This is what my last rendition on the 3B looks like with Wilwood's Chrysler type master, their proportioning valve and residual valves for four wheel discs.

 

Wilwood Disc Brakes 261-13269 - Wilwood Aluminum Tandem Master Cylinders

Is what is on the Jeep from stock a proportioning valve? Can I use that and we just put in the Residual Pressure Valve?

 

If you are still running the stock brakes, I can see no reason you can't use the stock proportioning valve. That said, the adjustable ones allow one to really fine tune performance and I would use the one that came with your master cylinder. It appears all those parts use inverted flare fittings and should be easy to plumb.

 

Jeep calls the factory valve a "combination valve." You'd find extensive discussion in the TSM if you'd looked, including cross-sectional diagram.

It's a combination because it includes both a proportioning valve, and a brake failure switch that activates the brake warning light if there is a pressure difference between the front and rear circuits. There is no residual valve - the disk brake Jeeps got a residual valve included in their version of a combination valve.

The proportioning valve holds off the rear brakes in hard braking, to prevent rear lockup. You understand that rear wheel braking should be proportional to the amount of weight transfer to the front, which depends on how hard the braking is (amount of deceleration). I presume you could use the factory valve and add residual valves for the front brakes, if there's no downside to a separate residual valve for each front wheel. As I recall, the combo valve also splits the front circuit to feed both sides, so in that case you'd necessarily need a pair of residual valves. You could also use the combo valve from a Wagoneer or later CJ, that includes a residual valve for the front wheels. This uses the same inverted flare fittings as your factory valve, in a similar configuration. Inline tube has these.

https://www.amazon.com/3-2-Proportioning-Valve-Mopar-VML101/dp/B009X20EAW

 

NB this is about half as much as I recall it selling for previously. Other sites show it discontinued. You might buy soon if you want this part.

 

Here's Mine......~$60 . All the rest is GM. Oh Yeah, Pirate 4X4 has a lot of 'em.