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proportioning valve and rear discs.

Cavalry

Sr. Member
Joined
Aug 25, 2001
Messages
786
Loc.
I HATE UPSTATE NY
I am swapping in rear discs. I have a 77 P-valve kickig around somewhere. Its unlikely that it will give me the proper valving I need. OK fine I will pick up a aftermarket valve. I assume I would connect this to the rears only. What do I do for a brake imbalance switch?
 

SaddleUp

Bronco Guru
Joined
May 23, 2004
Messages
9,655
Loc.
Vancouver, WA
Cavalry said:
hmmm will have to go and look at the old one.. thought it was a p-valve+switch too???
As far as I know none of the EB's had proportioning valves. All they had was the H-Block and the only purpose of it is to detect a difference in pressure from front to back to turn on the brake warning light. On mine I have never run a proportioning valve and that includes drum/drum, disc/drum, and now disk/disk.
 

76Broncofromhell

Bronco Totalitarian
Joined
Jul 30, 2001
Messages
4,226
Loc.
Reno, NV
Go on Summit and buy an adjustable one. The H-block is kind of a dumb idea anyway as I can tell when I have no pressure in one of the lines (e.g. the brake pedal going to the floor).
 

74BroncoCO

Bronco Guru
Joined
Nov 3, 2004
Messages
2,374
Or get the adjustable Master Cylinder and do away with all your prop or hblock stuff.
http://www.cpptalk.com/Hot.htm

That is what I want to do, and then I can dial it in. My MC needs replacing anyway and that's not too bad for the price, which reminds me, I should get one before they go up!

J.D.
 
OP
OP
Cavalry

Cavalry

Sr. Member
Joined
Aug 25, 2001
Messages
786
Loc.
I HATE UPSTATE NY
74BroncoCO said:
Or get the adjustable Master Cylinder and do away with all your prop or hblock stuff.
http://www.cpptalk.com/Hot.htm

That is what I want to do, and then I can dial it in. My MC needs replacing anyway and that's not too bad for the price, which reminds me, I should get one before they go up!

J.D.

just bought my 'vette one lol
 

74BroncoCO

Bronco Guru
Joined
Nov 3, 2004
Messages
2,374
Cavalry said:
just bought my 'vette one lol


Installed yet? I don't know a lot about how the brake system should be setup, but I am wondering how this thing works. Does it come with good instructions? Thanks!

J.D.
 

lars

Contributor
Been here awhile
Joined
Jun 29, 2001
Messages
3,038
Loc.
NorCal flatlands
SaddleUp said:
As far as I know none of the EB's had proportioning valves. All they had was the H-Block and the only purpose of it is to detect a difference in pressure from front to back to turn on the brake warning light. On mine I have never run a proportioning valve and that includes drum/drum, disc/drum, and now disk/disk.

They did, 76/77 only. Technically it's a "three way valve" or something like that, since it had a proportioning valve for the rear drums, the imbalance spool and a metering valve for the front discs that was supposed to slow the application of the disc brakes because apparently drums actuate more slowly.

I use a Wilwood adjustable valve. Cheap, easy to install (goes in the rear brake circuit) and can be adjusted for how much crap I have in the back of the Bronco. I have 4 wheel discs, for what it's worth.
 

74BroncoCO

Bronco Guru
Joined
Nov 3, 2004
Messages
2,374
So what's the rule of thumb for adjusting brakes? I know you want the front to do most the work, but say with an empty bronco, when do you want the rears to grab? Is the testing trial and error?

J.D.
 

SaddleUp

Bronco Guru
Joined
May 23, 2004
Messages
9,655
Loc.
Vancouver, WA
74BroncoCO said:
So what's the rule of thumb for adjusting brakes? I know you want the front to do most the work, but say with an empty bronco, when do you want the rears to grab? Is the testing trial and error?

J.D.
You want to be able to apply the brakes in a panic situation without one end or the other locking up before the other. When I first installed my front disks I almost did put one on mine (in the front brakes) because the front brakes were slightly too agressive. I.E. They would lock up just a hair ahead of the rear ones. It was very slight though so I never did anything with it. If I had installed one in the rear brakes as many here suggest then I would have really had problems with the front locking up first. I have rear disks now though and the brakes at both ends now lock up simultaneously. It can make it a pain to unload from my trailer if its wet though. Half of the time I drag the front off it sliding because having it work right for street driving means the front tires lock up a bit faster than the back.
 

natureboy300

Full Member
Joined
Dec 29, 2005
Messages
171
Loc.
livermore
74BroncoCO said:
So what's the rule of thumb for adjusting brakes? I know you want the front to do most the work, but say with an empty bronco, when do you want the rears to grab? Is the testing trial and error?

J.D.
A good method for doing that is to have the normal amount of gear in the bronco, then put a half tank of gas in, dial it in till both sets lock up at the same time. This means that when the tank is empty the backs should lock up jast a hair sooner and opposite with a full tank. This will get you close and you can fine tune it from there however you feel comforatable.

NB
 

MnkyBiz

Bronco Guru
Joined
Jan 17, 2004
Messages
3,758
Loc.
Northern VA/DC
I have a hydroboost, discs in front and in rear, and still use the old H block. My front & rears lock at the same time, so no reason to install the proportioning valve. Before you install, try it out!
 
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