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Old 09-02-2008, 09:32 AM   #1
gcburdic
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Brake Question

Hey Guys and gals,

I plumbed in my hard lines and hooked up the power booster and master cylinder this weekend for my disc/drum setup, BUT in a schematic provided, I noticed they had a 10 lb residual valve plumb for the rear drum brakes???...
I think I know why they did this to prevent rear wheel lock up, but I wasn't sure if I needed to do this or is it in the prop valve??

Anyone done this???...if so, got any pics and where did you install this??
on the prop valve or closer to the rear axle??

Any help is much appreciated!
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Old 09-02-2008, 01:19 PM   #2
gcburdic
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Re: Brake Question

here's a link to what I am talking about....thanks

http://www.mbmbrakeboosters.com/Tech...gurations.html

I have my power booster and MC on the firewall....
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Last edited by gcburdic; 09-02-2008 at 01:21 PM.
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Old 09-02-2008, 02:58 PM   #3
68gmsee
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Re: Brake Question

When I first read your post, I thought it may be something I wasn't aware off. Now I know for sure, it's something I wasn't aware of.

From the read part you posted, it looks like it's a performance type product for quicker stops???

I have never heard of this before but that doesn't mean it's not being used in some of these trucks. However, I'm not sure I understand why you would need a 10lb residual pressure component to keep the break shoes close to the drums. On my rear breaks, I just adjust them until they are barely touching the drums. That's about as close as you can get them for stopping purposes.
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Old 09-02-2008, 05:34 PM   #4
umwtnt
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Re: Brake Question

You normally only use a residual valve when the master cylinder is lower the the brakes. Like when the master cylinder is mounted under the floor boards. In our application there is no need for one. A 10 lb is used for drum brakes and a 2 lb is used for disc brakes.
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Old 09-02-2008, 08:17 PM   #5
cparman
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Re: Brake Question

residual check valves are for brake systems where the master cylinder is LOWER than the brake calipers or the wheel cylinders. IF you master is in the stock location you should not need them.
www.mpbrakes.com
I like these guys, and go to their web site, and to their FAQ tech help area and it will talk about check valves
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Old 09-02-2008, 08:47 PM   #6
LONGHAIR
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Re: Brake Question

The residual valve is "built in" to the stock stuff. It is only necessary to "add" one in a "custom" application with a bunch of aftermarket "race" parts.
The point of the residual valve is to keep some pressure in the lines because of the springs that pull them back to the "resting" position.
Calipers don't have springs, they just "relax" when you let off of the pedal. Too much line pressure would cause them to drag against the rotors
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Old 09-03-2008, 08:16 AM   #7
gcburdic
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Re: Brake Question

Okay guys....Thanks alot for your responses.....I was worried I had to get that residual valve plumbed in too....I am so darn close to getting my project rolling I can't stand it!!!.....

Thanks again
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