Is COTA hard on brakes? Ayep.
09-06-2016, 01:15 PM
#1
Drifting
Thread Starter
Is COTA hard on brakes? Ayep.
COTA with Chin last weekend. During the Happy Hour Saturday a car blew an oil seal. The driver was quick to respond and it happened right at T19, so he ducked into the pit, but the oil leak was bad enough that he spun sideways, blocking the pit in and then had a small fire. I was on the back straight when the red flag flew a lap after a new PB. Just before Happy Hour I noticed a loose oil dipstick from a fallen out bolt. I didn't want to risk an oil leak and was able to repair it. Notice the smoke after I stopped:
In real time I thought I had an oil leak and was going nuts waiting to get back to the paddock. Felt like forever, but it was only a few minutes. Upon getting back and inspecting, no oil anywhere and it dawned on me the smoke was coming from the wheel wells, not the hood. A friend, stopped on the other side of the track came up to comment about it. Note that this car has very good brake ducting and that was intact. The PFC 08 pads and Stoptech ST-40 calipers were working very well.
I normally do a cool down lap or 1/2 lap and I've never seen the brakes do this before. Ironically, on Sunday, my student during the last session made a decision to get off the track at T18, so no cool down lap. We rolled up to his friends and the brakes on his Turbo S were smoking the way mine had. Cringe worthy and cool at the same time.
Why cringe worthy, upon inspection Sunday morning, I found what is pictured below. Both left and right front rotors cracked in three places. They weren't long for this world anyway, but the no cool down sure didn't help them. The M3 spent Sunday on the trailer - a generous friend saved my Sunday by letting my drive his SRF - that will be another tread topic.
-Mike
In real time I thought I had an oil leak and was going nuts waiting to get back to the paddock. Felt like forever, but it was only a few minutes. Upon getting back and inspecting, no oil anywhere and it dawned on me the smoke was coming from the wheel wells, not the hood. A friend, stopped on the other side of the track came up to comment about it. Note that this car has very good brake ducting and that was intact. The PFC 08 pads and Stoptech ST-40 calipers were working very well.
I normally do a cool down lap or 1/2 lap and I've never seen the brakes do this before. Ironically, on Sunday, my student during the last session made a decision to get off the track at T18, so no cool down lap. We rolled up to his friends and the brakes on his Turbo S were smoking the way mine had. Cringe worthy and cool at the same time.
Why cringe worthy, upon inspection Sunday morning, I found what is pictured below. Both left and right front rotors cracked in three places. They weren't long for this world anyway, but the no cool down sure didn't help them. The M3 spent Sunday on the trailer - a generous friend saved my Sunday by letting my drive his SRF - that will be another tread topic.
-Mike
09-06-2016, 01:28 PM
#3
Drifting
Thread Starter
And yep, K1s with a 12mm spacer.
-Mike
Last edited by TXE36; 09-06-2016 at 01:45 PM. Reason: cooking not cooing
09-06-2016, 01:35 PM
#4
Rennlist Member
yes, those rotors are done, but thats not a track problem or a cool down problem, those rotors just became EOL.
you might want to try downshifting more , Certainly when you are coming to a stop in that kind of situation, as you wont need as much brakes to slow down. You did a routine 120 to 0 slow down and stop with no cooling afterwards... you might have bedded your brake pads a little if they hadnt seen that much heat before.
a couple of blips and shfts and you may not have even needed the brakes that much to slow down and stop.
ST40s are the same pads I use with the same rotor size. they take a tone of abuse. mine just lasted the entire racing season and havent shown a crack yet. you also might be growing out of the capability of the PFC-08s and might need to move up to the 11s. what did the pads look like?
you might want to try downshifting more , Certainly when you are coming to a stop in that kind of situation, as you wont need as much brakes to slow down. You did a routine 120 to 0 slow down and stop with no cooling afterwards... you might have bedded your brake pads a little if they hadnt seen that much heat before.
a couple of blips and shfts and you may not have even needed the brakes that much to slow down and stop.ST40s are the same pads I use with the same rotor size. they take a tone of abuse. mine just lasted the entire racing season and havent shown a crack yet. you also might be growing out of the capability of the PFC-08s and might need to move up to the 11s. what did the pads look like?
09-06-2016, 01:50 PM
#6
Drifting
Thread Starter
It also does just fine with PFCs on the stock rear calipers/rotors.
-Mike
09-06-2016, 02:02 PM
#7
Rennlist Member
Hand of God brakes - seriously. It is amazing how fast Bad Girl can stop. I was able go just a bit deeper than the 150 marker of COTA's T12, which is just in front of us - the red flag is being displayed at the T12 flag station. Car is capable of outbraking just about anything there, although I have to admit my student's GT3 could go as deep as the 150 and it's entry was at much higher speed.
It also does just fine with PFCs on the stock rear calipers/rotors.
-Mike
It also does just fine with PFCs on the stock rear calipers/rotors.
-Mike
stock usually works quite well in most all track /street conversions.what is with the NO gloves, short sleave shirt? how long have you been doing this? youre spinning, smoking, craking rotors and you think fire knows you are only "DE'ing" ? just having the gloves for better control is worth the price of the set!
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09-06-2016, 02:23 PM
#8
Burning Brakes
We cracked 3 sets of front rotors at Daytona with our Supra Chump Car. Never had cracked rotors in 6 previous races, but this was our first time using ST-43 pads.
So the next race, we used new rotors and R-4E pads. Pads were gone after 12 hours but rotors looked great. Put the ST-43 pads back on and the rotors cracked within 3 hours. ST-43 pads still look great.
We're still looking for a front pad that will last 14+ hours and not destroy our rotors.
So the next race, we used new rotors and R-4E pads. Pads were gone after 12 hours but rotors looked great. Put the ST-43 pads back on and the rotors cracked within 3 hours. ST-43 pads still look great.
We're still looking for a front pad that will last 14+ hours and not destroy our rotors.
09-06-2016, 02:42 PM
#9
Rennlist Member
COTA is among the hardest on brakes tracks there is.
09-06-2016, 02:46 PM
#10
Rennlist Member
We cracked 3 sets of front rotors at Daytona with our Supra Chump Car. Never had cracked rotors in 6 previous races, but this was our first time using ST-43 pads.
So the next race, we used new rotors and R-4E pads. Pads were gone after 12 hours but rotors looked great. Put the ST-43 pads back on and the rotors cracked within 3 hours. ST-43 pads still look great.
We're still looking for a front pad that will last 14+ hours and not destroy our rotors.
So the next race, we used new rotors and R-4E pads. Pads were gone after 12 hours but rotors looked great. Put the ST-43 pads back on and the rotors cracked within 3 hours. ST-43 pads still look great.
We're still looking for a front pad that will last 14+ hours and not destroy our rotors.
try them... you will not be disappointed.
however, i dont know what rotors the Supra has, but generally, they are very thin on the far-eastern econ-o boxes. sometimes if they are too thin, no matter what you do, a track like daytona can kill them. sounds like you put heat in and out of the rotors and it couldnt take it... the main problem with daytona is that you get things really hot and then relatively cool every lap... that expansion and contraction causes a thinner rotor to crack. Porsches come stock with 32mm thick rotors with great metallurgy qualities. you need to find this to help the rotors survive some uses.
Last edited by mark kibort; 09-07-2016 at 02:06 PM.
09-06-2016, 04:14 PM
#11
Rennlist Member
And with these kind of tracks, and there are a lot of them, brake management needs to be used. Plenty of cars are running much faster than this e36 with stoptech brake kit, with a lot less power and with MUCH smaller brakes and dont have any issues more than other tracks like COTA. (spec miatas run sub 2:45 with fastest being 2:41)
09-06-2016, 05:27 PM
#13
Rennlist Member
09-06-2016, 05:35 PM
#15
Rennlist Member
The straights are all followed by 90 degree or greater turns. You are going from whatever your car will do to a second gear turn. It is extremely hard on brakes.