Master Cylinder Bracket

[Mart]

The one Glennpm is showing looks a lot like the one I made for my 32. I think the use of the box section is a good idea.

Mart.

 

[Andy]

I am sorry but I did not read all the posts.I am going to address the ratio question.
You want full stroke on the master cylinder plus a little for flex. The total movement on the pedal is say 5 inches and the total stroke of the master cylindr is say 1.25 inches, you need to have a 4 to 1 ratio on the movements. Higher will not move the cylinder far enough and lower will be too stiff of a pedal, The arm for the pedal and the lever to the master cylinder both will move thru the same angle. You would need to have the arm lengths in the 4 to 1 ratio. If the pedal arm is 12 inches, the M/C arm would be 3 inches. Adjust to your dimensions.

 

[rich b]

^^^^
How does the pedal effort work out with the 4 to 1 ratio compared to the 6.4 to 1 ratio of a '39-'48 juice brake pedal using the same 1-1/16" bore Ford master. Thinking that is why the V-8 garage uses the smaller bore master.

On the other hand my kid has a couple of cars (and has built several more) with the early Ford master mounted so the push rod is just barely below the K member and an ear welded on the stock pedal and while I haven't driven them, they evidently work.

 

[Andy]

I was just trying to share some thoughts on getting the master cylinder so it is pushed all the way in with full pedal travel. Your dimensions are probably different.

 

[Charlie Stephens]

I don't think I ever calculated the ratio. I just made sure I had the same ratio that I measured in a '39 pedal assembly. I figured the guys at Ford knew what they were doing.

Charlie Stephens

 

[Mart]

That's a neat setup, there, Charlie.

 

[glennpm]

Nice use of a bellcrank design setup Charlie.


Glenn

 

[rich b]

I was just trying to share some thoughts on getting the master cylinder so it is pushed all the way in with full pedal travel. Your dimensions are probably different.

Your quite right to emphasize the importance of pedal travel and while Ian1932 is working with a single master cylinder here; it is even more important that full pedal travel is available for those that retrofit a dual master cylinder. We have come across several cases where this was not taken into consideration on the install and due to lack of available pedal travel there was no "safety factor" from the use of the dual master.

 

[V8COOPMAN]

I like this example to help understand what rich b and Andy are talking about. DD

 

[tubman]

Here's some interesting information. I have a 1999 F150 beater pickup. Being that it has spent its whole life in Minnesota (most of it in the twin cities area) it has some rust problems. It has factory dual circuit brakes with ABS. The brakes on it have always worked flawlessly. A couple of years ago, I blew a rear line that had rusted out. I had barely enough brakes to limp it back to my shop. Last year, I blew a front line. I had no brakes; none, zero. I have inspected and replaced all metal brakes lines and the brake hoses since then. An inspection of the fuel line surprisingly shows very little corrosion.

 

[Ian1932]

Glenn, That 3" number from the center of the pedal pin to the hole in the lever or to the center of the master push rod, Is this the best? Or do i want to shoot for the smallest lever length possible? Like 2-3/4" or 2-5/8" even? Thanks

 

[glennpm]

Hi Nick,

The smallest possible, but make sure that the arc swung by your lever length allows clearance between the push rod clevis and the bottom of the center-section front lip also make sure the lever doesn't hit the center-section.

The pictures of my lever with the brake pedal at the top, may help. Make a pattern out of cardboard. Tack the lever on and see how it goes.

Glenn