The Stovebolt Site Forums The Shop Area Driveline Advanced Design 1/2 ton dual master cylinder bracket upgrade

I have been slowly picking away at the 1950 project and have been working on the brakes but its taking longer than necessary because I haven't been happy with my choices out there. It seems that all of the solutions to mount a dual chamber master cylinder using the stock pedals require you to either; modify the rear cross member, or run a heim joint with a spacer to line up the new MC bore with the push rod. With some kits you have to do both!

I might be able to get over the cross member modification, but I just cannot get behind using a 3/8 bolt in single shear on such a safety critical item. Does this bother anyone else? It seems that companies like CPP sell the heck out of the conversion kits. Has anyone ever ended up with a bent or broken bolt there where it attaches to the brake pedal?

This bothered ms so much that I did some measuring, I think I can design a bracket that fits a new dual chamber MC under the floor, with the proportioning valve underneath, without modifying the rear cross member, and using the stock clevis and a lengthened push rod. It would also put the front chamber of the MC just under the old fill hole in the floor so you can just elongate that hole and not have to cut a new one further back.

Anyway, I'm just looking for some thoughts from you guys on whether this bugs anyone else and if anyone has solved it another way.

They use to sell a modified original bracket that you could mount a dual manual master cylinder to. But I don't see it available anymore. Would one need a proportioning valve with drum brakes front and rear?

John

On my setup I have the 6 lug CPP front disc setup so I do need the pro portioning valve. I want it to look stock from the outside with updated running gear.

I drew up my bracket last night and sent it to the fabricator for quote. The cost may be a wake up call.

RL, I was the same way with the heim joint and spacer and bolt, was not to liking. I am using a mustang 1" bore duel MC with a bracket that came with it. It is from ECI. I cut my original bracket and moved it towards the frame. This subject has come up before. Dad's 50 posted a photo of his MC bracket. His has been cut down . That is where I picked up the idea. I have tons of trouble with computers so I will not even try to post a photo. But if you look at Dad's 50's photos you can see what is needed. I have disks and drums the MC has a rear proportioning valve built in. A single standoff is in line for the disks. That way I did not need to worry about room for the proportioning valve plumbing. I missed my fill hole in the floor a little. Floor mat makes it look good.

I purchased the dual reservoir bracket from classicparts.com which is a CPP bracket. What I dislike about the bracket is the amount of flex that it has when I push on the brake pedal. I have the cab off of the frame and I have actuated the pedal by hand. The bracket flexes way too much for my comfort and I will be welding on some more support to beef up the bracket.

No booster
...link...

Yup, like that!

I'll try and post pics of my design tonight.

There is no flex on mine. I can't even see how there could be. This one?

http://devestechnet.com/Images/Restorations/1950B/D50b00028lg.jpg

Mine doesn't budge. It's made out of 1/4" steel and bolted securely to the original chassis bracket. I didn't go with the booster either.

Maybe the shaft is bottoming out inside the cylinder and you are putting too much pressure on the assembly. Once correctly adjusted, there is no movement. That was one of the things that sold me on the system.

Here are some screen shots of the solid works model for the bracket I'm cooking up. https://goo.gl/photos/Sc3tEj7C6LVvvpy58

I don't know who modified mine but I can use the existing fill plug in the cab. Comes in handy .
Not sure if you considered that in your design. It's something to look at.

The front chamber is directly under the stock plug. I was thinking of elongating it so I could get the cover off without crawling under the truck. I'll see how it looks when I install it. Thanks again for the photo links. Looks like I'm not the only one that doesn't like the bolt and spacer.

so in about 5 days it will be 3 months I'm wandering what you come up with because thats my next project for my 49 5 window