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I have a Scarebird setup which, as we speak, is plumbed from the dual master straight to the discs & drums, without any valves. I find the rears are too active.

I was looking at a combination valve but when I called to order it the tech at Jegs recommended an adjustable proportioning valve instead. Not sure I would have the temperment to go out and test and perfect the adjustment. Plus then I might have to add a metering valve and a pressure sensor... leak opportunities and it might start to look crazy in there, especially if I add a residual valve.

Would many of you take the tech's recommendation?
 

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I certainly wouldn't be buying no damn Chevy valve that's for sure.
If you want a stock style one, why not find a used brass one off maybe a later disc brake Galaxie?
 

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I have a Scarebird setup which, as we speak, is plumbed from the dual master straight to the discs & drums, without any valves. I find the rears are too active.
Strange. I thought the general consensus here was that "we don't need no stinkin' valves"... :confused:

I was looking at a combination valve but when I called to order it the tech at Jegs recommended an adjustable proportioning valve instead.
Do you think he is really a QUALIFIED TECH or just a phone salesman? :frown:
 

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I certainly wouldn't be buying no damn Chevy valve that's for sure.
:confused:

Why Not? Everything else on the car is GM?
 

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Not everything. Not now they're not. :)
 

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Be careful! Know what you are getting and what you're not when looking at valves. A combination valve includes a pressure differential valve. This valve will isolate either the front or rear brake circuit if there is a leak as a safety feature which is the reason for a dual circuit system. This was required by Federal Law in 1966(?) to eliminate the possibility of a complete brake system failure. The switch on these valves does not operate the rear brake lights, it triggers the brake warning light that warns that one of the brake circuits is malfunctioning (loss of pressure) and you are using only the front or only the rear brakes and needs immediate repair. The Summit valve shown in the earlier post is visually misleading and there are lots of others that do the same. Companies marketing this stuff walk a very thin ethical and legal line when dealing with brake system safety. Lots of misinformed sales people and literature. I have used the stock Ford combination valves on my cars. If you still have problems with rear brake lock ups, then a simple adjustable proportioning valve can be installed on the rear brake line after the combination valve and before the rear brake wheel cylinders. Puttster, the combination valve you have posted in the photo from Jegs is correct and has the valves needed to do this. The switch on top is for a brake warning light. If you just put in the simple adjustable proportioning valve shown in the other photo, you will be at risk.
 

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correct the one i posted link for...has the rear brake light pressure switch ...
not (brake warning light switch)...
 

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Be careful! Know what you are getting and what you're not when looking at valves. A combination valve includes a pressure differential valve. This valve will isolate either the front or rear brake circuit if there is a leak as a safety feature which is the reason for a dual circuit system. This was required by Federal Law in 1966(?) to eliminate the possibility of a complete brake system failure. The switch on these valves does not operate the rear brake lights. They trigger the brake warning light that warns that one of the brake circuits is malfunctioning and you are using only the front or only the rear brakes and needs immediate repair.

The Summit valve shown in the earlier post is visually misleading and there are lots of others that do the same. Companies marketing this stuff walk a very thin ethical and legal line when dealing with brake system safety. Lots of misinformed sales people and literature. I have used the stock Ford combination valves on my cars.

If you still have problems with rear brake lock ups, then a simple adjustable proportioning valve can be installed on the rear brake line after the combination valve and before the rear brake wheel cylinders.

Puttster, the combination valve you have posted in the photo from Jegs is correct and has the valves needed to do this. The switch on top is for a brake warning light. If you just put in the simple adjustable proportioning valve shown in the other photo, you will be at risk.
What he said... ;)

The Pressure Differential Valve was introduced in 1967 (FED MANDATE) and has to be used with a Dual Reservoir MC to have the feature operable.

If one decides to install an Adjustable Proportioning Vavle after an OEM valve, the PV section of the Combination Valve should be defeated.
 

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I have used the stock Ford combination valves on my cars. If you still have problems with rear brake lock ups, then a simple adjustable proportioning valve can be installed on the rear brake line after the combination valve and before the rear brake wheel cylinders. .
the oem style in your picture can be missleading as well...
(they may look the same, but you have get the one rated for your size vehicle)
you should not have to put a adjustable p/valve behind them....unless you installed the wrong one...

also the one i post link to...does separate front and rear brakes...
 

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the oem style in your picture can be missleading as well...

(they may look the same, but you have get the one rated for your size vehicle)

you should not have to put a adjustable p/valve behind them....unless you installed the wrong one...
Correct. And you will not know for sure what the calibration is until you do a panic stop on a slick road surface.

OEM does extensive engineering to ensure the correct PV for each vehicle.
 

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has the rear brake light pressure switch .
When the Combination Valve came through, the brake lamp switch was mechanical, i.e. mounted on the brake pedal lever.

If you want to use the old style hydraulic switch, you will have to add a fitting (ideally on the rear drum circuit).
 

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I have done front disc swaps on my 66 Ford F100 from a 76 Ford F150, 65 Galaxie from a 77-79 Tbird, and in the process of doing the Granada swap on my 57 Tbird. I stick with Ford parts and take everything from the donor car including the combination valve. Using the matched sets has worked so far for me without problems. I looked at Scarebird stuff but like the idea of using all Ford engineered parts that come from the same vehicle, hopefully to avoid the mix/match issues. Never used an aftermarket proportioning valve. In some swaps using the rear wheel cylinders from the donor car or its equivalent has been talked about but I haven't needed to yet. I put at least 30k on the truck and the same on the Galaxie since the swaps.
 

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Rag , have you used that one on your car?

My car is a mess. Previous owner had Granada front disks put on along with power brakes and dual resevoir. I bet the disk brakes are undersized as the Granada isn't close to 4k lbs. And it has a wildwood adjuster on the rear brakes only. No wonder it brakes like ****!
 

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I seriously doubt that it is the disc foundation brake changeover. The GRANADA swap has been used on heavy cars with much success. I am more inclined to believe it is in the actual installation.
 

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^^^ you could be on to something.



I also noticed the brake pads do not cover the entire face of the rotors. Meaning it doesn't use up the whole rotor in that section. I'll try to get a pic.

My brothers 65 cutlass with power 4 wheel drum stops a whole lot better.
 

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The combination valve listed earlier is available with various branding, such as from Speedway for $70. Or similar alternatives such as the Wilwood version I listed for this combo in another thread. Both blocks are for dual-piston masters, with rear proportioning and brake light pressure switch. Note you do not get a differential pressure switch (brake warning) nor metering valve for stop 'n go driving.

I suggest using an adjustable version over a factory one that was metered for a certain weight-range car with certain center-of-mass, tire combination, and brake area/pressure/diameter combination. They are not difficult to adjust for proper braking, but does need 2 people or driver and video camera, a stick of chalk or Bingo marker, and a safe paved area.

David
 

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Discussion Starter #19
Great resposes, thanx! Lars, the Summit valve has too much stuff I don't need, like the front outs and the stop light switch. Not having a dashboard warning light is not a biggie though because my master has a fluid level switch that is probably as useful.

Hardfor makes a point in favor of the combination. Plus Ilike that this kit provides a bracket. Is there a way of telling if the PV in the combo is adequate for a 4,000lb vehicle?

DanV if you know of a Ford equivalent, let me know, and how it's been working out for you...
 

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My car is a mess. Previous owner had Granada front disks put on along with power brakes and dual resevoir. I bet the disk brakes are undersized as the Granada isn't close to 4k lbs. And it has a wildwood adjuster on the rear brakes only. No wonder it brakes like ****!
Granada discs are 10.5in (same as every disc Mustang/Falcon/Fairlane from '65 to the Fox cars, the Granada and the last of the Mavericks had a different caliper mount, the '68-73 design was notorious for sticking and wearing pads unevenly), Torino/LTDII/late Bird discs are 11in, Galaxie discs are 12in.

Yes, as far as I'm concerned the Granada discs are too small for a Galaxie, the Torino setup is borderline but some people will accept that compromise to run 14in wheels. The Galaxie discs need at least 15s and if you're buying wheels you may as well go to 16s since quality 15in tire choice is poor.

An adjustable proportioning valve in the rear circuit only is the right way to plumb it.
 
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