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magicmarto
10-19-2018, 08:10 AM
Guys,
I am installing the pedal box at this time.
I have centered the elliptical bearing on the balance bar on the brake pedal.
In order for me to get the front, rear brakes at the right balance, I have to move the balance bar to the inside of the car.
This means, that there is more of the threaded balance bar to the inside than the outside.
Is this normal?
See the photo-I have disconnected the MC for the brakes in this image.
But in order to get the correct front/rear brake bias, this is how the balance bar ends up.....
See how much threads are to the inside vs the outside....

95802
Martin

Murd
10-19-2018, 08:26 AM
How did you determine this is the correct bias? The bearing is all the way to one side now, I can see the nut to the right of the pedal.

magicmarto
10-19-2018, 09:01 AM
when I hook up the MC and thread them in equally the rear brakes engage before the fronts-a lot.
I was trying to get them where they are almost equal. maybe the rear just a little before the fronts.

Am I wrong on this??
M

Murd
10-19-2018, 09:22 AM
Do you have the wilwood pedal box instructions? If not you can download them from their site I believe.
The bearing should be in the middle, the rear pushrod should be treaded further into the clevis, so the bar is staggered with the front longer. When you apply moderate pedal pressure you should have the bar then be even between the two MCs, when pushing hard the front will be compressed more and the bar will be at an angle again. Good diagrams in the instructions.
Moving the balance bar side to side changes pressure, not so much movement of which engages first. You won’t get any significant drag on the brakes until there is lots of pressure on both masters, it’s not like your rears are going to bite first.

edwardb
10-19-2018, 09:35 AM
Two things: (1) It's pretty normal to have to trim a little of the threads off the end of the MC pushrods to get the clevis's and pedals in the right location. Not sure if you're asking about that, but appears yours aren't trimmed and this might be part of what you're struggling with. (2) Don't draw any conclusions about how this works or what you observe when pushing the pedal down until you have fluid in the system and brakes bled. Assemble them per the instructions to start (centered, with the proper spacing which is very important) and then adjust later in the build if needed when you get to that point.

boat737
10-19-2018, 09:50 AM
Here's the Wilwood sheet. I had to read it a couple of times to really understand the dynamics of it all. Your picture looks off to me.

https://www.wilwood.com/PDF/DataSheets/ds252.pdf

OnlyAndy
10-19-2018, 11:42 AM
I have the same issue with pedal box in mt 33'. To get them to push evenly,,,,, by hand, no fluid, they have to be UNequal. But I have also been told not to get too worried about it this soon in the build. It seems the balance bar will ACT much differently when the system HAS fluid in it and is bleed properly. Thats when it get the Final adjustment. Realize this is what I READ and HEARD. I have never even seen one of these balance bar systems before this F5 33'.....

CraigS
10-19-2018, 12:03 PM
I have the same issue with pedal box in mt 33'. To get them to push evenly,,,,, by hand, no fluid, they have to be UNequal. But I have also been told not to get too worried about it this soon in the build. It seems the balance bar will ACT much differently when the system HAS fluid in it and is bleed properly......
All you do at this point is assemble per the instructions, being sure you have the proper clearance on either side of the black center piece. As EdwardB mentioned it is common to need to shorten the MC pushrods slightly. Set the adjustment so you have about the same amount of threads in view on both ends of the shaft.

magicmarto
10-19-2018, 12:36 PM
All great input
Thank you to all
Martin

davekp
10-19-2018, 06:12 PM
when I hook up the MC and thread them in equally the rear brakes engage before the fronts-a lot.
I was trying to get them where they are almost equal. maybe the rear just a little before the fronts.

Am I wrong on this??
M

You should not have more rear bias. A good way to set this for a street driven car is to do it in a big parking lot on a rainy day. Start with a lot of front bias- do some hard braking and add more rear bias until the rears lock first, then adjust to the front slightly.

mikeinatlanta
10-20-2018, 08:35 AM
Kind of repeating what others have said, but maybe from a slightly different angle. On a balance bar system, which brake engages first is irrelevant as it is a natural by product of the system and does not play into actual brake balance. It's all about pressure, and you will only know for certain when the car is up and running.

Start with the system centered as shown in the instructions. Once up an running, if you are able to get proper bias within the range of the balance bar then great, but if not, one of the masters will need to be resized. Which one will depend on how you like the feel. E.g. if you think the pedal is too firm and power too low, you would want to alter balance by installing a smaller master in the side needing more brake force. If you think the brakes are too strong and touchy, or pedal travel too long, then you would install a bigger master on the side with too much braking. That's the beauty of a balance bar system. You get it close with master sizing and dial it to perfection with the bar. IMO FFR should have made the masters easier to change once the car is done. Not sure how tough it is on the new cars, but was so difficult on my MKII that I rebuilt an entirely different mounting system for the pedal box. It now drops right out with four bolts from the bottom.

Boydster
10-22-2018, 09:04 AM
Craig and Paul both said it... set it up the way the instructions say.... balance bar centered and MC ends trimmed so you can get the proper start adjustment.

You are looking at a system with 2 different size MC's (applying different volumes) , different braking systems at each end (different # and size of pucks) with different weights and actions on the brakes at each end. You really cannot just look at it and balance the action on the MC's. That would throw your real braking action way out. Perhaps even dangerously.

Save the adjustment for an empty parking lot with weight, speed, CG shifts and multiple trials. Many people never have to adjust it at all.