When I fit my pedal I left about 1/4" of play between the rod and when it starts to push the piston in the master cylinder.

 

51 - I'm planning on running stainless line for the brake lines. I may even go with steel lines. Stainless costs more, but I think it's well worth it. Thanks for the advice on the inner bearing too.

 

Yea, that inner bearing adaptor can be warmed in your oven. Get a piece of pipe a little longer that the spindle. The adaptor will/should tap on real easy once heated. I used the steel lines, I took a coat hanger and bent it to a shape of each bend. Then bent the line the same as the wire. Don't forget the Stainless has to be flared at a different degree that steel.

 

Id go with the steel lines.. Cheaper if U make a error and have to replace a line. If U want flashy than make the lines U want first and then have them powered coated or painted.. Id at lest paint them to keep them from rusting.. And as 51 said SS has to be flared at a diffrent degree and U will need adpter for the master cyl and slaves cyl to match the flaring on the SS.. SS looks nice and last a long time.. but its not really for DIYers It can not be bent in a very tight radius and it can crack while being bent without you even seeing the cracks... I been there.. its no fun trying to find where all the air comming from.. I had to chase many leaks down on I/O drives..

 

Medathlon, thanks for the info on stainless lines, I feel much better now with my steel ones. Wayne

 

Jag,

If I may be so bold as to answer your question to George...

I think what George meant was that the pedal force required to generate the 1000 psi would be less with the smaller diameter piston.

As you stated, 2000 pounds of (pedal) force would be required to generate 2000 psi with a 1 square inch piston.

To generate the same 2000 psi pressure, you would have to put 6000 pounds of force on the 3 square inch piston
==> (2000 lb/sq. in.) * (3 sq. in.) =6000 lb

Clear as mud?

 

Adrian- good to see you back here again! I'm going to do my brake lines in the steel as it appears to much easier. I really like the idea of coating the lines to avoid future rust.

 

Hi Ed,


Good to hear from you also. I am about two weeks away from working on the truck. I am in the final stages clearing out my garage enough to get the truck in there and working on it. Looks like we are following the same path. My first task is to get the fuel cell and fuel lines in and then the brakes. I have power disks on all four wheels but the master cylinder is the wrong type. I may look up the guy in Long Beach one of posts pointed to.

I don't know how my reply to Jag ended up so far down. At the time I posted it, there was no answer from George. Oh well...
Cheers,

Adrian

 

Clear as mud alright LOL "ok, if a person is running the 1" piston. And they want more puessure, what size diameter would you say a person should drop down to, or how far down can you go.

 

It's going to depend on how much fluid your particular brake system requires to actuate and what the maximum stroke of your master cylinder is.

And now, for our Canadian friends, here are those three little words men find so hard to say

"I don't know",

as in I don't know how much fluid you need to move and what the stroke is on your master cylinder. That's something someone who works with brake systems all the time can tell you. A good kit would probably take those issues into account.

If you want to play around with it, let's assume you have picked the brake parts you are going to use at each wheel. Let's also assume you are working with one brake circuit to make it simple. This is probably not realistic if you have dual-circuit brakes, and that is another thing you'll have to play with.

Once you pick the hardware, the amount of fluid you need to move to actuate the brakes in each brake circuit is fixed. So is the required pressure in each circuit to get the proper braking action. I can't tell you what either of those numbers is for your specific system. Here are the general rules:

smaller piston, more stroke required to move the required fluid
smaller piston, more pedal travel to get the stroke needed to move the fluid
smaller piston, less pedal force required to get the required pressure

bigger piston, less stroke required to move the required fluid
bigger piston, less pedal travel to get the stroke needed to move the fluid
bigger piston, more pedal force required to get the required pressure

Personally, I would try to get a kit from somebody who's already done the playing around and figured out what size MC cylinder works well with specific brake hardware at the wheel. If you can't do that, you either have to experiment or find somebody that has the exact same setup as you so you can copy them. Enjoy!

 

Earl, I hear what your saying. Since I'm doing the disc conversion, I'm finding that to do this project correctly, I need a dual chamber master cylinder and get rid of the single on my truck, I'm also installing the 2 lb and 10lb valves and a proportioning valve for the rear drums. I've been told, (and I'm sure they may be incorrect) but ANY master cylinder will work as long as the bolt holds mounting it to the vacuum booster line up. Since I have no idea how much pressure I need to push through to make the brakes work, do I need to be concerned about piston size? I was planning on going to the boneyard (salvage yard) and pick up a good master cylinder that would fit my application. I'm concerned that if I go through all this work with running new lines, the connections, valves etc. I want to make sure I get the right master cylinder. In other words, I hate working on brakes and I only want to do this once. LOL.

 

I used a dual master cyclinder from a 73 F-100. Since its bolt pattern didnot match my 57 firewall, I had to make an adaptor. Made it from 1/8" flat steel. Make the adaptor fit your old master cyclinder mounting location, and make the adaptor accept the new master cyclinder. Mine worked great, I did have to shorten the master cyclinder rod about 3/8" . This was my orginal master cyclinder push rod. Hope I havnt confussed you, I am not very good at explaining things like this. Roy.