Brake pedal ratio
 

I has a 32 frame and pedals and will use a Ford 40 cylinder, and plan use a wat link, will lever/rato be Ok vs foot pressure ?
Se picture of a friends set-up but he use a modern 2 line ( do not kniw diameter )

Re: Brake pedal ratio
 

Re: Brake pedal ratio
 

If the bell crank between the pedal pull-rod and the master cyl push-rod is 1-1 ratio you should be good with a '40 master. If once it is together and you end up wanting a "softer" pedal you could always increase the length of the pull-rod side of the bell crank a little.

Re: Brake pedal ratio
 

Can't see the whole lever action picture of your friend's setup. With the poor picture, it's not possible to see the brake lever pivot point and how a push on the brake pedal is pushing the pushrod into the master cylinder

A common and good ratio for manual brakes is 6:1.
A '32 brake lever is 13" to the brake/clutch shaft center line, the "X" dimension below.


https://napaknowhowblo.wpengine.com/...1/pedal-1a.jpg
Your homework assignment is to post a sketch of your plan and /or your friend's :-)



Glenn

Re: Brake pedal ratio
 

There is a kit that I think is superb. It uses a bell crank mounted on an extended 32 pedal box shaft. This gives a push for the master cylinder way down low. I forget who makes it.
I really have a concern with what you have. The clevis is not as strong as other designs and the bolt has to be loose so it can turn.
I like to use use the strongest design for brakes.

Re: Brake pedal ratio
 

I agree with Andy about the engineering of you friend's set up. The pull rod from the brake pedal should have a regular clevis and pin connection to the bell crank instead of the odd connection in the picture.

I think the kit he mentioned is the V-8 Garage kit that bolts an extension to the stock pedal and mounts the master cyl bracket on the K-member. The only drawback is the low height of the master which is visible from the side on a fenderless car. There is another kit that mounts the master backwards on the front of the right leg if the K-member, that keeps it up and out of sight.

Re: Brake pedal ratio
 

I have not seen that kit but I have seen the original mechanical brake bellcrank used.The drivers side is stock but the master cylinder is facing backward on the passenger side. I thought about doing a car that way but the master cylinder was a bit close to the transmission. I was going to modify the arm on the bell crank for clearance.

Re: Brake pedal ratio
 

Hank, take a look at this HAMB thread https://www.jalopyjournal.com/forum/.../#post-8026903 I think the modification made by "flatoutflying" was worthy of note, simple and effective. If you were to use that modification in conjunction with a jack shaft attached to the back side of the "K" member, and mount the master cylinder in the wedge of the K member leg and the frame. I will mock this up and provide images on this thread in a few days. I don't think it's a good idea to have the master cylinder and or brake lines mounted below the frame rails.
Tom

Re: Brake pedal ratio
 

As an alternative here is the way I set mine up. I used the stock '32 pedals. I relocated the battery and the hole to add water to the battery is exactly where it is need to check the master cylinder.

Charlie Stephens

Re: Brake pedal ratio
 

Re: Brake pedal ratio
 

Seems the kit I mentioned earlier keeps the master on the left side.

Guess I was thinking of the pictures I have seen using the stock brake giz to operate the R/H mounted master as Andy described.

Anyway here is a picture of Salt City Speed Shop's '32 brake kit.

Re: Brake pedal ratio
 

Here's the link. I knew I had seen it but took a while to find it again.


https://www.fordbarn.com/forum/showp...10&postcount=7


https://www.fordbarn.com/forum/attac...2&d=1574805551
https://www.fordbarn.com/forum/attac...3&d=1574805551
https://www.fordbarn.com/forum/attac...4&d=1574805551https://www.fordbarn.com/forum/attac...5&d=1574805551

Re: Brake pedal ratio
 

Re: Brake pedal ratio
 

Late following up, I did not see any ideas.

I was at V8 Garage last month and their design is good but beside get the cylinder low it is not meant to use a Ford 40 cylinder said owner ( ratio will not be Ok for that cylinder diameter )

One way is to has the cylinder in front ok cross and use a std 32 lever system, but I think I like the cylinder behind.
I admit the watt link is not to great, here is another one I saw here in Sweden, se pics.

One think one dont like it weak here on brakes.
Plus I'm not a fan of modern ball links.
Its nothing wrong with the older U link.

Re: Brake pedal ratio
 

No ideas, are you serious??


Looks like you want to make your decision which you should.

Re: Brake pedal ratio
 

I’ll just mean I was late to check and right after it was no replys ( no I see it was ! - Thanks.

Here the other wat link pictures

Re: Brake pedal ratio
 

You could have the Ford master cylinder sleeved down to 7/8" from the stock 1-1/16". The pedal will stroke down closer to the floorboard than with the larger bore.