Front Brakes On Time

[marc hildebrant]

Group,

The original method for the Model A was to have the rear brakes on first, then the front.

Seems that at the time, people thought that if the front came on first, the car could flip.

Is there an advantage to have the brakes all come on at the same time ? Seems that that could help to stop better.

On my Harley, I always apply front and back at the same time.

Marc

 

[Tom Wesenberg]

I have my 28 adjusted so the rear come on first, but with hard braking all 4 can lock up. I would think all 4 being applied equally should be fine, and would probably give shorter braking distance.

 

[marc hildebrant]

Tom,

So....why did you set the brakes for back on first ? Was it to be original ?

Marc

 

[Kevin in NJ]

Page 79 of "Know Your Model A Ford"

"The Ford service brakes are so designed that 40 percent of the braking effort is exerted on the front wheels..(text not typed by me)...This distribution of braking effort not only gives quick stopping but also certainty of steering control."

 

[Tom Wesenberg]

Tom,

So....why did you set the brakes for back on first ? Was it to be original ?

Marc

I think some of it is due to the wear in my kingpins and bushings. I'm using a temporary front end while I restore the original, and the kingpins and bushings are very loose. I'll set the fronts up a click or two tomorrow and see if it's a bit more even. I checked the brakes with a temp gun after my last drive and found the fronts had no heat after easy braking.

 

[Marco Tahtaras]

The problem is the front and rear brakes don't actuate at the same rate. The front brakes actually come on faster but require more pedal pressure. You can make the front brakes come on slightly earlier than original but if you take it too far it will stiffen the pedal because you are fighting the front brakes to press the pedal far enough to lock the rears. Don't be afraid to experiment with the balance a little. Whatever you choose as your final adjustment, find a safe place to test "panic stops" at various speeds to be sure it tracks well.

 

[marc hildebrant]

Marco,

Is the different rate between front and back due to the rear "floating" and not the front ?

Marc

 

[Jim/GA]

Marco,

Is the different rate between front and back due to the rear "floating" and not the front ?

Marc

No, it has to do with the combination of all of the lengths of all of the levers that connect from service brake cross shaft to the shoes. That includes wedge in front and cam in back. The total leverages are different (by design) between front and back, hence different "rate" for the same pedal travel.