The Stovebolt Site Forums The Shop Area The HiPo Shop Dual master cylinder part number

I'm almost to a point to where I would like to go ahead and order a dual master cylinder for my 52 3604. Anyone got a part number for one that will work with the original pedal assembly and be located in the same place as the original?

I've checked the Tech Tip from Cletis, but it doesn't say exactly what year the MC came from nor the part number for the bracket. I'm sure they've changed since his tip, but it would be nice for a starting point for cross referencing.

I'd be interested in that, too. The only set-ups that I have seen require a special mounting bracket.

http://www.classicparts.com/1947-59-Dual-Master-Cylinder/productinfo/71-201/#.Vcj4l51Viko

http://www.classicparts.com/1947-54-Master-Cylinder-Adapter-Kit/productinfo/71-984/#.Vcj4e51Viko

Scott, PM Terry_B. He did the setup on his 53 so he may remember what it was and where he got it.

Tim, looks exactly like what I want....But the required* adapter kit is currently out of stock

I only say that it's required because I don't have the ability or trust to make my own.

Martin, I sent one to Terry B..No underscore in the name. You might know him from what his profile says

Tim,

What do you think about this one? I've never heard of this place and can't find much information about if they'd do a price match with Classic Parts or not. Think it would work? Add a proportioning valve later on if you go disc for the front?

f18delta,

That one looks closer to the one I bought several years ago. I never installed it, so I can give no opinion.

Maybe someone who has installed a similar set will reply.

It states: 3/4 ton?

Their 1/2 ton unit is listed for less.
Maybe someone can explain - they show the same photo of parts.

I installed it not that long ago. Works perfect, but if you want a booster on it to make braking easier, you will have some work to do on the crossmember. I decided to try it without the booster first, so that is exactly the setup I used. That works with the MC that was linked earlier in this thread too.

Of course there is more to it than just the bracket. A dual MC works so that half of it is for the front, the other half for the back. You will need a proportioning valve to help with braking balance. If you look at the Brothers Truck Parts catalog, its in there and specifies the 1/2 ton.

http://www.brotherstrucks.com/prodinfo.asp?number=DMC5954
http://www.brotherstrucks.com/prodinfo.asp?number=MSTR900
http://www.brotherstrucks.com/prodinfo.asp?number=VLV4772

That is the exact setup I have. Lots of work getting the brake lines set up, also I went with front disc brakes, so needed residual valves too.

Is a proportioning valve really necessary in an all-original-spec drums (front and back), and all original diameter brake line diameters, and all original wheel cylinder piston diameters.

No harm using one and fiddling with it, but is truly necessary?

The original components were made to provide an appropriate balance/proportioning (having been designed with different front/rear brake line diameters & front/rear wheel cylinder diameters/bores).

I do not know about residual valves. I read that some dual master cylinders come with them and some do not.

It is necessary since you don't want the front and back using the same pressure. The valve gives a bit more favor to the front brakes and a little less favor to the rear. Even with stock diameter brake lines. That is how I understand it, but someone else chime in please.

Residual valves are 4 pounds for disc and 10 for drum. They are not necessary for drums all the way around. They keep just (said amount) of back pressure on the system so its ready when you are. I had to put them on my disc front/drum rear setup.

I do not agree, if the brake system is original specification: the different original-diameter brake lines (front and rear) and different original diameter-bore wheel cylinders (front and rear), provide appropriate/adequate proportioning.

Isnt some of that out the window when you cap the T on the passenger side to put the back lines on a separate MC circuit than the front, then create a separate line to the front? Its like having two separate MC's. One is harder to push than the other, so this makes them the same again? I do not know for sure, but would want to find out before going to the trouble.

Got mine here. All parts there, works great, quick shipment.
Phil

https://www.performanceonline.com/Master-Cylinders-Proportioning-Valves-c-1059/

From my experience, both pistons in the dual MC are the same size. So if the rest of the system remains stock, a proportioning valve is not necessary.

Deve,

That link for the Brother's stuff is for the 1/2 tons only, correct? This 3/4 ton seems to have a lot of special needs that are harder and harder to find. If I had the money, time, space, and wanted to be on the road quicker, I swear I'd drop an S10 frame under this sucker and be done. Now that I think about it, it might be cheaper to do it that way and not have to worry about suspension and changing out the brakes and hubs. Gonna be stubborn on this one though.

The first link given by f18delta is for a 3/4 ton truck.

They also have kits for 3100 trucks - I think I posted a link to a set in a post above

Honestly, I do not know if the Brothers offerings are 1/2 ton exclusive. I was not aware of any difference, but that doesn't mean there isn't any. Give them a call and check.

I have pictures of the 1/2 ton version if anyone wants it. PM me