When I go onto the track my brake pedal is all the way up. After 15-20 min of hard braking the pedal is considerably lower. I still have good brakes but my foot is a lot closer to the floor. Any thoughts on this? I'm not adding fluid and I don't need to bleed to get my full pedal back- just some rest. Thanks

 

How old is your fluid? What pads are you using?

The first thing to do would be to flush and upgrade the fluid to ATE Super Blue or Gold, or the Motul stuff. Second, upgrade the pads - Pagid Orange seems to be a fave. Third, improve the brake cooling by adding a cooling kit. Fourth - I dunno - buy bigger brakes?

 

Morning Bruce,
I second Thom F above.
What car are we talking about?

Sounds like insufficient cooling, old fluid and maybe pads. Check and fix first.

From your symptoms the brake system sounds healthy, and I do not suspect the general system (calipers or m/c) to be the culprit.

As a second option I would also check the rubber hoses between the calipers and the body - after a run when they are hot, just don't burn yourself! When you return into the pit after a run, lift the front and remove a front wheel. Keep the engine running and have someone press the brake pedal hard, look and feel for flex in the hose, maybe a replacement / upgrade is required.

Still not happy - bigger brakes next.

Lastly, 20 min. on the track is good going, and if your really use your brakes a spongy pedal will be evident with most stock systems.

Who cares, if it stops and you enjoy yourself, keep going.

Best regards, Tom

 

Sounds like you definitely need to upgrade your brake fluid - if you're suffering pad fade, the pedal will stay high and go hard, and you will have little or no braking. If the pedal goes to the floor, you are suffering fluid fade and the pedal will literally go to the floor with very poor braking!

Regards
Eric

 

You don't need bigger brakes. If you saw what I do with my car on a track while using stock brakes, you would be convinced. But I maintain my brakes like fighter aircraft are maintained. First, change all the brake fluid. Run either ATE super blue, or Motul 600. Next change the pads to a high performance pad. Pagid orange are the best. If at this point the problem isn't solved, remove the dustshields on all sides. Those are the tin plate brake warmers that are behind all the rotors on the car. At the same time, put in some high quality stell braided brake lines. That should do it. If not, make sure the calipers are in 100% working order. And I mean 100%. I have seen too many people dump money on some other calipers thinking the stock ones were insuficcient for their application, when the originals weren't even working up to par to begin with. All of the above mods WILL do the job. I know because I run my car very hard at the track in temperatures bordering 110. I have a friend that kept having brake problems with his car even after getting his calipers rebuilt. He thought he needed brake ducts. I told him BS, give me the money. But I also told him to remove the dustshields. Next time at the track, problems again. I saw that he still hadn't removed the *&%#*$@ dustshields. Next time at the track, same problem. Then two months ago I woke him out of bed early in the morning and went to his house with my toolbox. I removed his dustshields and installed steel braided brake lines. I did it because I was tired of being disturbed from my comfortable chair between sessions at the track to help him with his brakes. Sure enough, next track day he was driving like a man possessed with no brake problems. I don't like dustshields even when they have a design that aids in cooling. The reason being that they will not help when the car is stopped. As a matter of fact, they will impede the little airflow from ambient wind from getting to the rotors. These mods will work. Just make sure you use line wrenches on the hard brake lines so you don't strip them when removing the calipers and the rotors to get to the shields. Also, the rear caliper is a little tough to remove due to the tight area.

 

You have received great advice from your friends: Here is my summary and I never had track fade problems: Remove dust shields, flush with Super Blue, install stainless steel brake lines, install turbo master cylinder, rebuild calipers, install cool brakes, install S aluminum calipers up front, change pads (Cool Carbon or?) to appropriate racing pads, bleed brakes before every weekend, bleed after the weekend....you are home free.

 

I installed the turbo master cylinder with my SC brakes, and decided I didn't care for the greater pedal pressure required (more like manual brakes vs power brakes). Solution? Install 930 brakes which are wonderful. Fresh brake fluid and piping some cooling air in keeps them fade free. Don't have to worry about fade during a two day event. However, you don't need to install bigger brakes to avoid brake fade, they just help a bunch.

 

I've been happy with the 19mm master cylinder, even with Turbo brakes fitted. The 'stabbing' braking of the 23mm cylinder offered less 'controlability,' in my opinion.

Click here: