Residual pressure valve for rear brakes
When I researched the front granada brake swap several years ago, I was told on the Ford six forum all I needed was a disc/drum MC and adjustable prop. valve. Since then I was told that not installing a rear drum residual pressure valve is the reason the rear brakes aren't working (they still look almost new after several k. miles) and my front brakes lock up, even with the prop valved adjusted all the way.
I don't remember the group installing one on Gary's car when we did the brake swap that day - or maybe I just missed it. I just want to clarify that's what I need to do (and anything else) to get my system working the way it's supposed to.
BTW, I'm going to have a leakdown test done on the car at a new shop in Bellevue called Blue Oval Ponycars this week www.blueovalponycars.com - please keep your fingers crossed that my problems are due to just valves, and not rings :)
No Prop Valve on Gary's Conversion
Thor,
We did NOT install a proportioning valve on my conversion. After the conversion, I still need to press pretty hard on the brake pedal to stop. I did some "panic stop" testing and found that the rears lock up first, so I know the rears are working. In fact, I'm wondering if I got the wrong MC (non-disc-brake type) and the rears are doing most of the braking. Don't know how I'd check that though....
I got a book on brake systems and it says you only need a residual pressure valve if your MC is LOWER than your rear wheel cylinders. It's to keep the fluid from flowing out of the wheel cylinder back to the MC.