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Proportioning valve?

All right, I give up on the brakes on my '55 Stude. They are as perfect as perfect can be mechanically, but I still have a rear lockup issue. Matter of fact after burnishing them a little with the car on jackstands, the issue is actually WORSE. Car stops like a big dog in reverse though :)

Question is this... do those knob style prop valves like wilwood et. al. sell give zero pressure reduction with the knob all the way out? OR do they start at some preset pressure drop? REason I ask is I don't think that I need a whole lot of pressure drop to make this system work properly, but it's just dangerous the way it is.

nate

(still don't understand why with all factory style components I'm having this problem...)

Reply to
Nate Nagel
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Could you have air in the lines to the front or maybe in the brake master cylinder's front section? Was the master ever bench bled? If you run the master dry when changing brake parts, sometimes you have to remove it and bench bleed it before it will give even pressure out again.

Most modern proportioning valves are called combination valves that set off a red light in the above situation of air in one side of the brake circuit. You don't have that now.

I am still suspicious about the size of the back shoes. If they are too big they throw the braking pressures all off. The levering action will be off and when it comes to lever action, they are pretty fine tuned.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

I'm still using the stock single circuit master cylinder so even if there were air trapped in the master it would be affecting both circuits equally... I really wanted to get everything working well with the stock setup before I started messing with any modifications. I have thought about converting to a dual circuit MC but obviously if I'd thrown that in the mix I'd really be lost now.

I hear ya, but at this point I don't see a choice but to throw a prop valve in there as I don't know anyone that will "arc" the shoes for me, the only way to get them worn in is to drive the car which I can't safely do at this time...

nate

Reply to
N8N

You could arc them yourself. Get some self adhesive 200 grit sandpaper and stick it inside the drum. Rotate the drum by hand and use the parking brake to apply SLIGHT pressure while sanding the shoes. They will then match the arc of the drums.

Reply to
Steve W.

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