4 wheel disc master cylinder?

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cu440da

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Are there any options for a 4 wheel disc master cylinder for swaps? I am on the verge of ordering a Wilwood rear kit and got to thinking about what the options are for a master. What have you guys used or heard of being used?
 
4 wheel discs on the 55 in my signature. Fronts are volare rotors and camaro / s10 calipers. Rear are ford explorer 8.8 discs. I use a volare manual master cylinder designed for disc / drum with an adjustable proportioning valve. It works fine. I have been told, and can confirm through experience, that new master cylinders no longer use the drum brake residual pressure valve. The setup works great.
 
Are there any options for a 4 wheel disc master cylinder for swaps? I am on the verge of ordering a Wilwood rear kit and got to thinking about what the options are for a master. What have you guys used or heard of being used?
1987 dodge diplomat or 87 Chrysler, works pretty well, maybe a hair more pedal pressure than I`d like, but they are manual brakes!
 
I always thought the reason for the disc master when doing a conversion for drum to disc was the lack of a residual pressure valve (and a slightly different bore diameter) If you run a disc drum master isn't there some sort of risdual pressure valve stil on the rear circuit? If so, I'd remove that from the master itself and then run an adjustable proportions valve like the wilwood unit.
 
In days gone by there was a residual pressure valve in drum brake applications. Its purpose was to hold a small amount of pressure in the system in order to keep the wheel cylinder rubber cups expanded and sealed. Wheel cyinders of today no longer need this as they have different cups, steeel back up plates and / or different shaped internal springs which hold the rubbers expanded. New master cylinders and most reman cylinders, in my experience, no longer have the valve.

I too wondered about the bore diameter for discs versus drum. The master cylinders mentioned above are engineered for disc / drum applications and have the same bore diameter throughout. Works just fine i a disc / disc application.
 
You didn't mention anything about your vehicle (truck?). If you don't have a booster, you want an MC w/ a small bore. I use one w/ 7/8"D bore in all 3 60's Mopars (95-99 Breeze w/ ABS). Many here like the mid-80's Dodge truck MC (rockauto). Both are 2-bolt aluminum, so need a 2-4 bolt adapter plate (ebay) and can buy "plate + MC" for ~$95 on ebay. You may have to re-terminate your tubes if the tube nuts don't match. Don't go past ~2000 unless you want to deal w/ bubble-flare ports (not hard, youtube). If the disk setup and tires are designed perfectly, you don't need a proportioning valve. Otherwise, an adjustable p.v. in the rear tubing is smart, assuming you adjust it in a wet parking lot - fronts skid just before rears.

You can infer the answer to your main question - MC doesn't really map to drums or disks. All the MC does is produce pressure, and the same pressure in front and rear circuits. Old 4-bolt MC's did have different reservoirs for front disk vs drum cars. All newer 2-bolt MC's have a single reservoir for both, so maybe doesn't matter, though there is a wall between them in the reservoir. You might check on rockauto if a different PN for 1990+ vehicles w/ disk/drum vs disk/disk setups. I doubt it, but don't flame me if wrong. Either MC would work as long as you don't let the reservoir run dry on either side.
 
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Old 4-bolt MC's did have different reservoirs for front disk vs drum cars. All newer 2-bolt MC's have a single reservoir for both, so maybe doesn't matter, though there is a wall between them in the reservoir.
That's what I was looking for. I was concerned about the tiny drum reservoir being used with discs. Sounds like a newer master is in my future.

Thanks.
 
I have wilwoods all around (and an extra rear kit...).I used the three parts listed in the pic and a wildwood adjustable prop valve. the distribution block was recommended by RightStuffDetailing p# PV01

20150907_094100.jpg


20150920_190342.jpg
 
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