Hard Braking Issue -

[pbeatty]

Having strange brake situation on track when I am trail braking for a turn and the brake turns hard and the brakes didn't respond - happened multiple times and slid off track since the car wasn't slowing down - only happened in trail braking after a high speed long straight. All the other corners braking responded normal -

Car in sport mode, no loss of power, no codes.

Brake Booster issue?
Brake fluid issue?
Brake line issue?
ABS / stability control issue?

Help please -

I have owned the car for 4-5 years and really haven't ever had an issue -

 

[Dialcaliper]

Stock brakes and pads?

If I construct what you’re saying right, I’m hearing you’re braking into a turn. Things are going fine, car is slowing, and then at the end of the braking zone/trail braking, the pedal stays firm but you just have no braking authority even though you keep pushing harder?

My guess is that you’re overheating the pads and experiencing pad fade which can be pretty confusing and even terrifying in the wrong corner entry.

Once you start driving hard, especially with any sort of TC engaged, even sport mode, the car uses the brakes quite a lot, which will keep the average pad temperature higher. The peak pad temperature spikes after a hard braking zone, and when you exceed the temp range, pad coefficient of friction takes a nosedive even if it is fine after a cooling phase

For any sort of track use, you *must* turn TC all the way off. If you start driving hard with sticky tires, you may eventually start overheating brakes even with TC off and need to look at upgrades

Everyone thinks of brake fade in the context of a long slow hill descent dragging the brakes, where they get hot and stay hot and just stop working, or fluid boiling which tends to stay elevated.

But on a circuit track, your brake rotors and pads are constantly heating and cooling through massive temperature swings, and when you hit the limit of your pads, it will rarely be at the beginning of braking (especially when they’ve had a long high speed straightaway to cool down) but will always be midway or towards the end of braking when pads are at their hottest. And also when it’s the scariest.

Step 1 is learn to drive, at least on the track with traction control full off. If you still want some help managing wheel spin, get a stage 1 (or stage 2) tune that has Cobb’s timing-only traction control available (dizzy, stratified and many other AP tunes can have it enabled)

Step 2. The stock pads are very good street pads - you won’t find many that are a better compromise, but you may want to consider getting some dedicated brake pads (or a pad/rotor set) for the track, even if it means swapping them out for more livable street pads. It will give you a chance to inspect your brakes and make sure everything is peachy before going to the track.

 

[pbeatty]

Hey Dial,

You constructed the situation correctly - Yeah on a couple corners it was pretty scary flying off the track at pretty high speed, luckily there was plenty of room for correctly and slowing down. I only had done about 1/2 my session but called it a day since I didn't want anything or anyone to get hurt / damaged.

I have EBC yellow pads, I can't remember the rotors - I first thought it could be brake fade or gloss but there is 0 smell getting out of the car and no smoke around the pads / rotor -

I figured it could be related to the traction control potentially confusing the ABS and the stability control into thinking that I'm on any icy condition or something like that if there was a bump in the road or if there was too many inputs confusing the system.

The tune is a good idea I hadn't thought about.

 

[Dialcaliper]

Hey Dial,

You constructed the situation correctly - Yeah on a couple corners it was pretty scary flying off the track at pretty high speed, luckily there was plenty of room for correctly and slowing down. I only had done about 1/2 my session but called it a day since I didn't want anything or anyone to get hurt / damaged.

I have EBC yellow pads, I can't remember the rotors - I first thought it could be brake fade or gloss but there is 0 smell getting out of the car and no smoke around the pads / rotor -

I figured it could be related to the traction control potentially confusing the ABS and the stability control into thinking that I'm on any icy condition or something like that if there was a bump in the road or if there was too many inputs confusing the system.

The tune is a good idea I hadn't thought about.

That sounds a lot like my experience with pad fade on the track before I ended up upgrading things. Modern metallic and carbon kevlar pads don’t seems to stink like organic street pads, and with the heating/cooling cycles on track, your balljoint boots, grease and other really smelly things that get hot alongside the sustained heating of traditional “brake fade” aren’t getting as hot on track.

 

[pbeatty]

That sounds a lot like my experience with pad fade on the track before I ended up upgrading things. Modern metallic and carbon kevlar pads don’t seems to stink like organic street pads, and with the heating/cooling cycles on track, your balljoint boots, grease and other really smelly things that get hot alongside the sustained heating of traditional “brake fade” aren’t getting as hot on track.

Thanks - Appreciate the help -