Weak Brakes after Track Day

[BigShow1960]

After tracking my car the brakes are not very sharp. This was my first ever track event which was at the Mid Ohio Sports Car Course. I really noticed the braking difference because I just got back from vacation where I rented a convertible A6 Camaro.

A week prior to track day I had my dealer change brake fluid. The pedal was never squishy, so I don't think that there's a gas bubble in the brake lines. The brakes don't pulse, so the rotor aren't warped. The track day air temps were cool, in the 40s and the first day was mostly wet. I only had three dry sets where I worked the breaks hard.

I had a lot of trouble changing my street braking habits to threshold breaking. I wanted to brake or I was braking a lot more than my instructor wanted me to. After my last set he said something like "your going to need to get better brake pads if your going to take your car to the track more", which I interpreted to mean, "you brake too much".

So, I'm going to schedule an appointment with my dealer to look at the brakes.

My question is Is it normal for heavy track day braking to dull brake performance and will or should braking response return to normal after XXX miles?

[KaBoom1701]

I cooked my V6 brakes the first time I went with my LFX.....it's what prompted me to upgrade to SS brembos on my V6 when I had it.

[SPCBA]

I don't know any info about your brakes. Did you have pads and fluids and lines for your brakes that are capable of operating at a road course temperature? If not...

[Crash76]

I smoked my stock zl1 brake pads at thunder hill last month... Can't imagine v6 brakes trying to road course...

Resurfaced the rotors and have new hawk 60 pads ...

Thunderhill this weekend ... Back for more

[jamestown]

Originally Posted by BigShow1960

After my last set he said something like "your going to need to get better brake pads if your going to take your car to the track more", which I interpreted to mean, "you brake too much".

So, I'm going to schedule an appointment with my dealer to look at the brakes.

My question is Is it normal for heavy track day braking to dull brake performance and will or should braking response return to normal after XXX miles?

I think he may have actually ment that you need better pads for track work. No hidden meaning. It is not normal for track pads to have dull performance after tracking. Street pads are not designed for repeated stops on hot rotors. You probably glazed your rotors a bit - it will probably go away but if you should take action or not to fix them depends a lot on how bad they are.

[Og Neon]

Having run Mid Ohio a lot, and based off your eval, I think you rode your brakes too much. So you glazed/over heated your stock pads and fluids. I would also suggest changing out your brake fluid for a higher temp fluid because stock pads and stock fluid on a 4k lb car is not going to do very well. I recommend swapping over to Motul RBF 600. I would try to bleed your calipers for now and re bed your pads in.

[MJanowich]

I think 2 things are happening. First, you should be using a brake pad specifically designed for the track. There are a LOT of varying opinions on which ones are best, but for me I've been happy with the Hawk HP+ on my stock (engine) SS automatic. They're easy to find and aren't too expensive. Faster cars and drivers probably need better pads than what I run. I also have brake ducts installed with helps a lot with heat management.

Second, you're probably slowing down too much before the turn in. That's just more heat and wear on the brakes if you're slowing down to say, 35 mph when you should be turning at 45 mph. I have a habit of doing this too. Ask your instructor next time to work with you on turn in speeds.

So, with that in mind, you probably over cooked your stock brake pads. I'd take the car to a trusted mechanic and have him look at the pads and rotors and see if you need new pads or not or if you need to have the rotors resurfaced.

Out of curiosity, when the dealer changed your brake fluid, what did they replace it with?

[BigShow1960]

Thanks all for the comments.

Byers Chevy, south of Columbus replaced the brake fluid. I asked for a high temp fluid if they had it. I don't know what they used; the FP-Number on the ticket is M0C06001, but I suspect that's just the work code for a brake flush. They are going to check my brakes Friday.

Due to personnel commitments I won't be able to go to the track again this season so I'm not going to spring for track pads. My plan for upgrading brakes is to buy a 2017 1LE at the end of the year or early in 2017.

Air temps were relatively cool so the track temps had to be very friendly. Over heating brakes probably had more to do with my poor attempt at track driving. I feel that I got only got turns 1, 3, 4 and 5 (end of the back straightaway), down reasonably well, even drawing some praise from the instructor. I'm sure those are the easy turns. I never felt like I had tun 2, madness, and the carousel at all right. I braked kind of hard in Thunder valley once and my instructor freaked out.

http://www.caranddriver.com/features...course-feature

[Synner]

GM doesn't sell or stock high temp fluid, saying if you have it doesn't mean you will install X, Y Z. You need to inspect your pads and flush your fluid with a DOT 4. I'm sure you boiled it and you may have overheated the pads which makes it possible to damage them.

Changing pads won't stop you from overheating your brakes due to bad habits, you need to learn from what your instructor tells you or you will repeat this scenario with whatever you upgrade to. Braking longer but softer increases heat in the system, it doesn't decrease it. You want to brake quickly and then return to cooling mode when off the brakes. Overall the v6 brakes are inadequate for track days on a 2 ton car so I wouldn't upgrade them anyways even if you planned on keeping it longer, I would upgrade the system to SS or ZL1 based upon track time anticipated.

[Norm Peterson]

Originally Posted by BigShow1960

I had a lot of trouble changing my street braking habits to threshold breaking. I wanted to brake or I was braking a lot more than my instructor wanted me to. After my last set he said something like "your going to need to get better brake pads if your going to take your car to the track more", which I interpreted to mean, "you brake too much".

You were almost certainly starting to brake too soon and too gently. Braking later and harder does take a little practice and some confidence.


Braking into China Beach (T4 on the Pro circuit, T7 on the club circuit with the chicane) works the brakes hard, as you're slowing from the fastest part of the course on a downhill run for a turn that you probably weren't going through at a whole lot more than low-50's.

Needing better pads is as simple as jamestown said it was. Stock street-intended pads, particularly on cars with base-level brakes and no cooling ducts, aren't built to handle the extreme temperatures that result from repeated heavy braking from high speed. A 40°F ambient isn't all that much cooler than 75°F when your pad temperatures are spiking well up into the hundreds of degrees F.

My question is Is it normal for heavy track day braking to dull brake performance and will or should braking response return to normal after XXX miles?

Possibly. I really can't speak for OE pads because I won't run those things on the track, but even the milder track pads don't always have quite the same 'bite' for the first few stops come the next morning. Track pads - I've been running Carbotechs, variously in XP8/XP10/XP12 - will come back, but I can't promise that base OE-level pads will.

You'll need to have the pad friction surfaces inspected for signs of melting and other kinds of deterioration, and that's in addition to seeing how much friction material thickness is remaining (I generally don't go below about 1/8" in purely street driving, and most places won't let you start a track day out with less than 50% of original thickness). Check your rotors for heat checking as well, and replace them if you can catch a fingernail in anything that isn't normal circumferential scoring.


Norm

[BigShow1960]

Thanks again guys. It will be a while before I can try your suggestions.

[BMR Sales]

Originally Posted by BigShow1960

Thanks all for the comments.

Byers Chevy, south of Columbus replaced the brake fluid. I asked for a high temp fluid if they had it. I don't know what they used; the FP-Number on the ticket is M0C06001, but I suspect that's just the work code for a brake flush. They are going to check my brakes Friday.


http://www.caranddriver.com/features...course-feature

This was probably the Problem. I personally like Motul 660

[L99CAMA2011]

Tell you what. You have a V6. At least upgrade to a SS Brembo brake setup and stainless brake lines with MOtul, Castrol SRF, you can run the pads I run that also are very good on the street for our heavier cars, the Hawk HT-10s. They needed 2 sessions at LimeRock to get up to proper operating temps. Not as good as DTC 60s or up but still very good. My brakes actually feel stronger after track days.

[Crash76]

Just put dtc 60s on my zl1 couple days ago... Holy brake dust haha... Burnished them in an my wheel looked like they had 20k mi on them haha... Made a ton noise slow speed braking... Until I put grease on them and the rear plates from my stock brakes...

About to track next two days...

Most dust I've ever seen after 10mi of driving... Definitely don't street them...

And I run motul 660 with goodridge SS lines