56 3100 Brake upgrades, need advice

[samdjr74]

Hi All,

I want to finish up my brakes next month, so far I've upgraded the frpnt and rear suspension so I'm running GM disc's on all 4 wheels. Next is the master clynider/brake booster. Here's where I need some help. Should I go firewall mount or frame mount? What's the advantages and disadvantages to each? Besides the master cylinder what else do I need to buy? I see adds that say I need a pressure valve, combo valve, etc, do I need them? I don't have the stock pedal but the frame mount for the original master cylinder is still intact and good.

Any help would be great, thanks,
Sam

[mr48chev]

On that particular truck the only advantage of a frame mounted master cylinder and booster would be a cleaner firewall and engine compartment. If you are into the clean firewall look and don't like stuff hanging out to block the view of the engine, go under the floor, If you really don't give a rip if people see your mc and booster hanging off the firewall, put it there where it is a lot easier to get to.
The truck came with a firewall mounted master cylinder and swing pedals so I would imagine it would be a lot easier to mount it on the firewall and a lot easier to check and service it.

[samdjr74]

Thanks, but what about the proption values and residual pressure values, are they needed? Also my truck came with the mc mounted on the frame so mounting to the frame would be eaiser but to the forewall wouldn't be too hard as well

Originally Posted by mr48chev

On that particular truck the only advantage of a frame mounted master cylinder and booster would be a cleaner firewall and engine compartment. If you are into the clean firewall look and don't like stuff hanging out to block the view of the engine, go under the floor, If you really don't give a rip if people see your mc and booster hanging off the firewall, put it there where it is a lot easier to get to.
The truck came with a firewall mounted master cylinder and swing pedals so I would imagine it would be a lot easier to mount it on the firewall and a lot easier to check and service it.

[OrrieG]

Mr. 48 summed it up. On my 59 I put it underneath, I wanted the clean firewall and use of the stock pedal. Bad news is in the future filling and replacement will be more of a hassle. Look at post 13 and 39 in my build thread to see the basic layout. I built my own brackets and used the 74 master cylinder and Prop valve with a hotrod 8" vacuum booster.

[low57]

Keeping the master cylinder and booster underneath the cab in my opinon would be easier simply for the fact that if you go the firewall route then you have to cut into the firewall and also brace up under the dash where the pedal assembley will go. As far as using residual valves you need to use one for the front and one for the rear if the master cylinder is under the cab and I believe that if you have four wheel disc 2 pound residual valves are needed. Have you thought about going the hydroboost route under the cab? I am in the process of putting a hydroboost under the cab of my 57.

[samdjr74]

I didn't even think about a hydro boost, what are the benefits of a regular booster?

Originally Posted by low57

Keeping the master cylinder and booster underneath the cab in my opinon would be easier simply for the fact that if you go the firewall route then you have to cut into the firewall and also brace up under the dash where the pedal assembley will go. As far as using residual valves you need to use one for the front and one for the rear if the master cylinder is under the cab and I believe that if you have four wheel disc 2 pound residual valves are needed. Have you thought about going the hydroboost route under the cab? I am in the process of putting a hydroboost under the cab of my 57.

[ChuckDriver]

I went with the underfloor mount from Master Power Brakes. My truck has a camaro clip up front and a chevelle rear with a big drum brake kit. I followed their plans and used the prop valve and both 10lb and 2lb residual valves. The brakes work great, just like that of a camaro! Here are some links to their site and setup diagrams.



http://www.mpbrakes.com/uploads/docu...rumdiagram.pdf


http://www.mpbrakes.com/uploads/docu...erfloorpdf.pdf


http://www.mpbrakes.com/products/pro...product_id=192

[ChuckDriver]

Here's a pic of my setup.

[blackdiesel]

Well, I like the clean firewall also. But on my truck and grandpa's truck we have the M/C and booster on the firewall, and dad has the CPP uint under the floor, all have 4 wheel disc. Mine and grandpa's truck stop on a dine and give change, but dads, you better not tail gage or you will be buying a new grill. I dont know if it's a bad booster or if it's because his is a 8" and ours is like 11". Under the floor is alot easier.

[MrSinister]

I had the underfloor and then went with the firewall mount on my truck and I definitely like the firewall mount. the firewall mount puts the pedal in a much more comfortable position and I had alot of problems with exhaust routing and tranny mounts with the underfloor mount. both of them were from cpp and they both were easy to install and are well made.

[blackdiesel]

Mrsinister, Did one work better that the other, or just pedal position? Where the booster both the same size?

[MrSinister]

the underfloor booster had an 8" single diaphram booster and the firewall came with a 8" double and it did make a big difference. but it was mostly the better angle that i was looking for, it's going to be much more comfortable especially since i plan on driving the snot out of it when i'm done