GT-40 pedal box

[Timothy Piecuch]

I'm fighting a balky brake pedal on a difficult to access pedal box with wilwood brakes. It appears as though there is a torsion spring in the pedaland the rod running through it appears to have both heim joints bound up or threaded on it. Can anyone enlighten me as to the specifics of this assembly?

 

[Mike Drew]

Might want to move this post over to the Superformance section to get some SPF-specific knowledge working on it for ya....wish I could help, but I don't have a clue. Perhaps share some photos of what you're talking about? The answer might be obvious to another SPF owner.

 

[Seymour Snerd]

Can anyone enlighten me as to the specifics of this assembly?

The SPF pedal cluster has a "balance bar" arrangement whereby a bar attached to and perpendicular with the two brake master cylinder shafts is pushed on near its center by the brake pedal. Where exactly it pushes is adjustable by rotating the 3/8"-25 threaded shaft at the right end, and doing so will move the "push point" right or left. This allows a very fine adjustment of the distribution of force between the front and rear master cylinders.

Perhaps if you define "balky" more precisely we can help. There are other threads on issues with this unit, this being the most notorious:

http://www.gt40s.com/forum/superformance-gt40s/24720-brake-bias-bar.html

It has a few pictures that should provide insight into how it's put together.

Also, if you're going in through the footwell you can get better access to the unit by opening up the chassis forward of the footwell. A quick description of how to do so is here:

http://www.gt40s.com/forum/superformance-gt40s/29204-changing-pedal-location.html#post299608

and here is a more detailed one:

http://www.gt40s.com/forum/superformance-gt40s/29204-changing-pedal-location.html#post329618

Since the pedal pivots are at the bottom one way things can go down hill is moisture and debris getting into the pedal pivots or all the rest of the mechanism between your foot and the master cylinders. Another possibility, of course, is the bias bar spacers (or lack of same) as in the first thread above. And then maybe you fluid's all gummed up from the somewhat off-hand arrangement for capping and connecting the brake reservoirs. If the reservoir hoses are leaking (as they have for others) that fluid could be running down into the pedal cluster and causing trouble when combined with dirt and moisture. I'd probably start by checking if the pedal pivot is OK (free and without play). Then verify that pedal motion is properly translated through the balance bar to master cylinder motion.

Lynn Miner, SPF Pioneer, discovered early on that without a jam nut the brake balance bar could adjust itself. Perhaps yours is adjusted all the way to one side. See

http://www.gt40s.com/forum/gt40-tec...-wheels/23873-spf-gt-brake-bias-bar-lock.html

Let us know what you discover.