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      01-30-2011, 11:22 AM   #23
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Originally Posted by O-cha View Post
Brake less, it's just that simple. System has it's capacity. It's possible for a race car to be able to use their brakes freely (not even all of them), not going to happen easily in a street car. Even once the OP has his stoptechs on they will have their capacity, and it's still very achievable for a 3,200 lb car on rcomps.

Not many people install forced brake cooling in street cars.
Look, I've been saying from the very first post in this thread pretty much the same thing. Do you have a problem reading? Don't be under the false assumption that you can take this particular production car with the stock system (even with pad and fluid upgrades) and push it hard and expect things to hold up.

Having said that, some production cars are better at brake cooling out of the box than others due to the design of the cooling vanes of the rotors and how flow is directed at/through the wheel well (I think some p-cars have a simple part that snaps onto the suspension for instance to direct air toward the inside of the wheel for instance, etc.)
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      01-30-2011, 11:53 AM   #24
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Look, I've been saying from the very first post in this thread pretty much the same thing. Do you have a problem reading? Don't be under the false assumption that you can take this particular production car with the stock system (even with pad and fluid upgrades) and push it hard and expect things to hold up.

Having said that, some production cars are better at brake cooling out of the box than others due to the design of the cooling vanes of the rotors and how flow is directed at/through the wheel well (I think some p-cars have a simple part that snaps onto the suspension for instance to direct air toward the inside of the wheel for instance, etc.)
No, you said specifically "don't give me any of that "don't overuse the brakes line"" And that's exactly what I'm giving you. If you're overheating them you are overusing them. They cannot take constant balls out laps, and if you are you're overusing them. Saying otherwise means you assume that BMW should have fit the car with brakes that could and that's totally unrealistic. You have to conserve them, period.

And again, to drive the point home, even stoptechs or brembos on the car with Rcomps can be "overused" without forced air cooling in place. So even if BMW fitted them which is COMPLETELY unrealistic we would be in the same boat.
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      01-30-2011, 12:13 PM   #25
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No, you said specifically "don't give me any of that "don't overuse the brakes line"" And that's exactly what I'm giving you. If you're overheating them you are overusing them. They cannot take constant balls out laps, and if you are you're overusing them. Saying otherwise means you assume that BMW should have fit the car with brakes that could and that's totally unrealistic. You have to conserve them, period.

And again, to drive the point home, even stoptechs or brembos on the car with Rcomps can be "overused" without forced air cooling in place. So even if BMW fitted them which is COMPLETELY unrealistic we would be in the same boat.
The sentiment I was referring to is, "Go fast but use the brakes less," which doesn't add up. If your brakes are overheating, you need to use them less, which means you will turn slower laps. You and I seem to be interpreting the term "overuse" differently in that sense.

I never said BMW should have done this or that apart from pointing out that their stock systems seem to be relatively underperforming compared to the competition.

I never claimed aftermarket kits would solve the issue. I said, "The critical variable in sustained operation is not really the mass of the rotors, but their ability to transfer heat into the environment, which ultimately boils down to cooling and forced convection."
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      01-30-2011, 05:16 PM   #26
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The sentiment I was referring to is, "Go fast but use the brakes less," which doesn't add up.
I completely disagree with this as a blanket statement. As new drivers get better, they do in fact get faster by using the brakes less. It's a fact that new-to-tracking drivers do overuse the brakes because they have neither the confidence nor the ability to brake later and carry more speed through the turn so they brake early and long thus going slower and over-using the brakes. Not to mention, newer drivers leave DSC on which is also going to overuse and overwork the brakes thus resulting in slower average speeds and a potentially failed braking system.

As drivers get better, they do use use the brakes less and less until they reach the terminal velocity that their car/equipment is able to sustain through a curve. You then increase the car's ability to handle additional speed around the curve via suspension modifications, weight-loss, etc so you can then brake even less and maintain even more speed through. Then you rinse, repeat, and do the process all over again until you reach the maximum capability you and your current equipment can achieve...and then you buy a lighter, lower, higher-horsepower car.
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      01-30-2011, 06:14 PM   #27
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I completely disagree with this as a blanket statement. As new drivers get better, they do in fact get faster by using the brakes less. It's a fact that new-to-tracking drivers do overuse the brakes because they have neither the confidence nor the ability to brake later and carry more speed through the turn so they brake early and long thus going slower and over-using the brakes. Not to mention, newer drivers leave DSC on which is also going to overuse and overwork the brakes thus resulting in slower average speeds and a potentially failed braking system.

As drivers get better, they do use use the brakes less and less until they reach the terminal velocity that their car/equipment is able to sustain through a curve. You then increase the car's ability to handle additional speed around the curve via suspension modifications, weight-loss, etc so you can then brake even less and maintain even more speed through. Then you rinse, repeat, and do the process all over again until you reach the maximum capability you and your current equipment can achieve...and then you buy a lighter, lower, higher-horsepower car.
The basic physics behind all this has to do with the conservation of energy principle. First, define what using the brakes "less" means. What does it mean really? What does it mean to carry more or less speed through a corner and how is that related to using the brakes more or less?

So, a novice driver is more likely to overheat their brakes because he/she used "more" brakes compared to an advanced driver? Is that what you are saying? If it is, that's pretty much false.

The only way to objectively quantify what it means to "use" brakes is to consider how much kinetic energy is being converted to heat during braking, which is why your car slows down.

A novice driver will convert less kinetic energy to heat during braking in general, and therefore will use the brakes less. That's because he/she will aproach the braking zone at lower speeds (despite the fact he/she will exit at lower speeds). Note that kinetic energy is proportional to the square of the velocity.

Total energy converted to heat during the braking event = 0.5*mass_vehicle*(v_initial^2-v_final^2)

where

v_initial is the velocity when you apply the brakes
v_final is the velocity when you release the brakes

To think through this, let's take a braking zone before a corner where you normally do a 200kph --> 80kph. If you were to corner faster and exit that zone at 110kph instead, you wouldn't be braking less because since you are cornering faster you must now be approaching that zone at a higher straighaway speed, say 220kph (a guess; this would get very complicated if we got into drag losses etc). If you do the math on kinetic energy change for those 2 scenarios, you'll see that the faster scenario will result in more kinetic energy loss (as heat), so you used more brakes (about 8% more actually according to my quick calculations; for a 215-->110 scenario, it is ~2% more).

This is simply why, at any given trackday, in similar cars, almost none of the novice drivers overheat their brakes whereas some of the faster and more advanced drivers might.

If this wasn't the case, as people got faster, their demands on the brake system would decrease and not increase, and they wouldn't have to shell out big money to upgrade their brakes. Club race cars could run on completely stock systems, etc.

Of course, there is another dimension to this, which has to do with how much heat the rotors are transferring into the enviroment, and the faster you go on the straights, the more heat your transfer out, but that doesn't seem to be an overwhelming factor (especially for cars that do not have direct forced cooling) since if it was, again, faster drivers would not need to upgrade their brakes and racecars could run on stock system, etc.
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      01-30-2011, 08:05 PM   #28
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my head almost exploded
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      01-30-2011, 09:59 PM   #29
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my head almost exploded
Well, the above scenarios are rather simplified (at the risk of oversimplification) and they don't prove anything by themselves since I guessed at the higher top speed and didn't account for differences in braking cooling rates. In the faster scenario, the higher top speed (v_initial) is a factor of how much faster the driver get can on power to exit the corner and how the drag losses increase with speed (in addition to the higher v_final).

What I am saying is that things should play out in a similar manner in the real world. Otherwise, all you would need to do to avoid overheating your brakes is to lap faster, which is contrary to what happens in the real world.
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      01-31-2011, 01:35 PM   #30
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Lucid is 100% correct. The difference here, is some of you are talking about "learning" the process to go fast, but Lucid is talking about if you're already near the capabilities of your car, i.e. if you're good enough to consistently lap at a very high speed.

What I've found, is if you find that the "less" you brake the faster you go, you've simply not found the proper braking point/threshold on a consistent enough basis. Meaning you're over-braking for most of the brake zones and giving up unnecessary speed through the turns. So if you're going slower at the beginning of the turn, you'll be going slower through the middle of the turn and you will in turn be going slower by the end of the straight. The end result is there won't be enough cooling available in the slower section to dissipate heat. It's easy to see how a beginner to intermediate driver can potentially be braking too much to overwhelm a brake system.

But, the ultimate physics equation does not change. The faster you go, the more heat you will generate in the brake system. Some of you, if not most, will eventually get fast enough to experience this. So the question here is, how exactly do you alleviate the additional heat generated by faster laps? There are two ways to solve this. One is to upgrade the equipment. The other is by extending your braking zone, start your braking early and do the majority of your braking early in the braking zone to allow your system a longer period of time to cool down. The key in the 2nd method, is you MUST only do the same amount of braking but do it early enough so you can carry the same speed through the turns.

So what's the difference between the two methods? Method 2 is slower. Meaning you're potentially giving up .1-.2 second per braking zone depending on how "weak" your braking system is. On a complicated track this can be as much as a second per lap slower. For time-trial and racers, that is a freakin' eternity and the difference between podium and coming in LAST. So they'll go ahead and choose option number 1 by upgrading their system to a point where they can no longer overwhelm their brakes no matter how long and how fast they drive. And that's why you'll also see racers and time-trial dudes often pick up a second or two on brake upgrades ALONE.

The only point I will disagree with Lucid on, is the way temperature is measured and when/how it's measured as compared to the system's capacity. It is true that the boiling/flash point of typical DOT 4 fluid is around 400 F, and if you don't do a cool-down lap and come in and measure the rotor temp, you'll likely see anywhere between 500 F to 1,000 F depending on how hard you're pushing and where the pit is located. It doesn't necessarily mean that the brake system is being overwhelmed.

Now, if brake fluid boil at 400-600 F, how can a system that measures up to 1,000 F be okay? Well, it takes a while to boil the fluid. The brake rotors may be at 600 F, but the fluid will take a while to reach that temp, if the rotor continues to radiate that 600 F then eventually the fluid will boil and the system will be compromised. However, a well designed system should allow the heat to evacuate quickly and bring that temperature down rapidly if the rotor continues to turn (if vented, thus drawing air and heat away from the system) and not allow the fluid to reach boiling temp.

Unfortunately we don't have F1 like budget to have live telemetry on brake rotor temp, but I think what most of us will find is that the rotors on typical street cars used on track will reach around 250 F on straights (pulling numbers out of my ss here) and as much as 1,000 F in the braking zones. Obviously, if the heat is allowed to build up and stay with the rotors then the number will climb and eventually cause a brake system failure, but I'll bet it'll be the brake PAD maximum operating temperature that'll be exceeded first.

Typically "fluid" fade problems stem from cars that does not get the opportunity to get a nice cool down lap before it comes in, or does not get a sufficient break between sessions (i.e. back to back sessions where heat is allowed to build up within the fluid). But to the rest of Lucid's point, I agree 100%...And not because O-cha disagrees.
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      01-31-2011, 01:46 PM   #31
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This is simply why, at any given trackday, in similar cars, almost none of the novice drivers overheat their brakes whereas some of the faster and more advanced drivers might.
To this point, I must offer this nugget of wisdom.

First timers or very novice guys don't often overheat their brakes because they're not carrying enough speed. What I find is, it's the beginning-intermediates to intermediates that start to experience overheating problems because they've figured out how to go fast, but they haven't figured out how much to slow down yet.

My famous analogies follows.

Beginners are slow in the turns, slow in the straights.
Beginner/Intermediate to intermediates are slow in the turns, fast in the straights.
Advanced Intermediates are fast in some turns, fast in the straights.
Advanced guys are fast in all turns and straights.

So the problem with brake overheating lies in the beginner/intermediate level, in which they're consistently over-slowing for the turns, thus building up a ton of heat in the brakes, while ballsy enough to be full throttle down the straight (or have figured out enough of corner exit to carry speed through the last 1/3rd of the turn). The end result is overheating brakes due to not enough cooling available in the first 2/3rd of turns and retaining just enough heat in the system to eventually overwhelm it.

Another analogy. This goes to everything I "teach" at the track. The learning process goes in cycles.

Beginners almost NEVER overheat their brakes.
Intermediate guys almost always will experience overheating brakes at least once.
Advance intermediate guys rarely overheat their brakes.
Advance guys can and will overheat their brakes at will.

I once made a comment on another forum about how the tire noise and exhaust noise will go in and out of sync as you learn how to drive faster, and your hands will move faster and slower and then faster as you learn to drive faster, and while there are universal truths to driving fast, in order to go as fast as possible every single one of those universal truths will be broken.

Braking and heat management of the brakes is part of that learning process, IMO.
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      01-31-2011, 03:59 PM   #32
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So the question here is, how exactly do you alleviate the additional heat generated by faster laps? There are two ways to solve this. One is to upgrade the equipment. The other is by extending your braking zone, start your braking early and do the majority of your braking early in the braking zone to allow your system a longer period of time to cool down. The key in the 2nd method, is you MUST only do the same amount of braking but do it early enough so you can carry the same speed through the turns.
Right, the second method is pretty much what one must do if one needs to manage the thermal issues without upgrading equipment.

Another way to look at this is in terms of acceleration and deceleration "zones." By definition, when you are accelerating, you are picking up momentum and building up kinetic energy, and when you are decelerating, you are losing momentum and converting kinetic energy to heat.

The fast driver will have a much longer acceleration zone than the slower driver because he/she will get on power much earlier (coming out of the turn), and he/she will brake later (by more consistently threshold braking at the limit and trail braking when appropriate). So, the faster driver will spend more time on power per lap. Some of that "extra" energy pumped into the system is used to overcome the increased drag due to going faster, some of it is scrubbed with the tires by being more aggressive at corner entry (I took me some time to get that concept and you kind of think it is not possible until you see someone else do it and start being more aggressive yourself), and some of it ends up in your brake system.

So, to manage the brakes, one needs to shorten the acceleration zones like you are saying and limit the top speeds. In other words, get off the power earlier than you could have, brake earlier and with less line pressure, but shoot for same the corner entry speed. Alternatively, you can just get off the power and let the car coast for a second at the end of the straight before braking (well, coasting is really decelerating since there is drag).

In terms of where to measure temperatures: you are correct that there are several things going on. These are the main components that can fail:

1. Brake fluid
2. Pad
3. Rotor
4. Caliper (mainly the pistons)
5. Brake lines

Any of the above can fail independently. And, yes, measuring rotor surface temperatures will not tell the whole story. Fluid temperature can vary depending on the design of the caliper and pads (dimensions and materials). But it is very difficult to objectively determine the local temperature of the fluid in the caliper--I don't know of a system that can report that. Pragmatically speaking, all one (a weekend warrior) can proactively do is to monitor rotor temperatures and try to infer if the fluid might be at risk of overheating or not. Of course, one can and should be reactive and back off if the pedal starts getting soft or if the stopping distances increase due to pad fade.

I think one should just generally back off if rotor temperatures after a cool down are ~600C. That's not a very accurate way of diagnosing anything, but it's better than not paying any attention to what your brake system is doing and then being surprised by something going horribly wrong.

Also, I learned not to put too much faith in the pad manufacturer's specs. The HT10s that self-destructed on me where supposed to be good for ~750C, and I don't think they got there, but I have no way of knowing the peak on-track temperatures (the rotors were at ~600C at the paddock). In comparison, I had Pagid RS19s on the day before that, and even though they had a slightly lower temperature rating, they held up. Well, they cost twice as much though.

Finally, operating at such a high temperature range cannot be good for the rotor itself as far as how it is stressed thermally.

OP, did you ever figure out what happened to your brakes?
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      01-31-2011, 10:31 PM   #33
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      02-01-2011, 12:05 AM   #34
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Thanks all, yes yes.... very lucky. Love that gate. May buy that gate a present.

The car just went in this (Tuesday) morning so I don't know any more just yet. To answer some qu's I was using Motol 600 and Hawk HPS pads. Yes... I know I shouldn't have been pushing those pads hard and probably not tracking them at all, especially with the supercharger, but they were what I had at the time, and they were only one track day old and one month into their lives. It is also possible that I didn't give them enough time to bed in initially, and I didn't visually inspect to make sure the transfer layer had gone across.

The failure happened only about 4 laps in to the third session of my day. Also there was a break for lunch and an excursion to get fuel before that third session. FWIW the pad wear sensor didn't go off until after the spin.

Yes, there were signs. And I wasn't ignoring them, I just didn't realise how serious things were getting. There were signs earlier in the day too, but it was really wet for the first session, and greasy for half of the second, so I didn't push them THAT hard, although both of those sessions were a little over 30 mins each. I think lucid's comments about an IR gun are spot on and that is on my list, along with being more proactive about my brakes and generally being more cautious about things I already know may not be up to scratch.

I don't want this thread to turn into Hawk HPS bashing though. There is enough of that in other threads, and because of the bedding in question it doesn't really add anything new to all the chatter. If anything I think this thread is a reminder to be more awear of your brakes in every way you can, and also to make sure you have exit plans for all corners, especially the ones you are going into fast. Knowing I could go through that gate and being able to accurately visualize that part of the track before I got there allowed me to plan and I believe saved my ass. Being more proactive about my brakes would most likely have stopped the whole thing happening in the first place.

Have been very interested reading all this discussion and will have to read it again to digest. In reference to Hack's levels I think I would be around "Beginner/Intermediate to intermediate".
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      02-01-2011, 12:28 AM   #35
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This is some scary stuff man. Glad everything is ok. I''m surprised that civic, even supercharged, has that much of a performance edge over your s'charged s54. Probably really light.
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      02-01-2011, 01:32 AM   #36
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This is some scary stuff man. Glad everything is ok. I''m surprised that civic, even supercharged, has that much of a performance edge over your s'charged s54. Probably really light.
Thanks man. I don't think he would have had an edge normally. You can see I came out of that last corner in big mess and in 4th gear instead of 3rd where I should have been. But before that I was keeping up fairly easily with a bit of a lazy line and early turn ins. I didn't follow him long enough to be sure though, maybe he was just warming up. He did mention having spent large to get it where it is.
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      02-01-2011, 03:22 AM   #37
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Ohhh. You are lucky...
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      02-01-2011, 03:51 AM   #38
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great save there!
lucky!
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      02-01-2011, 08:56 AM   #39
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Thanks all, yes yes.... very lucky. Love that gate. May buy that gate a present.

The car just went in this (Tuesday) morning so I don't know any more just yet. To answer some qu's I was using Motol 600 and Hawk HPS pads. Yes... I know I shouldn't have been pushing those pads hard and probably not tracking them at all, especially with the supercharger, but they were what I had at the time, and they were only one track day old and one month into their lives. It is also possible that I didn't give them enough time to bed in initially, and I didn't visually inspect to make sure the transfer layer had gone across.

The failure happened only about 4 laps in to the third session of my day. Also there was a break for lunch and an excursion to get fuel before that third session. FWIW the pad wear sensor didn't go off until after the spin.

Yes, there were signs. And I wasn't ignoring them, I just didn't realise how serious things were getting. There were signs earlier in the day too, but it was really wet for the first session, and greasy for half of the second, so I didn't push them THAT hard, although both of those sessions were a little over 30 mins each. I think lucid's comments about an IR gun are spot on and that is on my list, along with being more proactive about my brakes and generally being more cautious about things I already know may not be up to scratch.

I don't want this thread to turn into Hawk HPS bashing though. There is enough of that in other threads, and because of the bedding in question it doesn't really add anything new to all the chatter. If anything I think this thread is a reminder to be more awear of your brakes in every way you can, and also to make sure you have exit plans for all corners, especially the ones you are going into fast. Knowing I could go through that gate and being able to accurately visualize that part of the track before I got there allowed me to plan and I believe saved my ass. Being more proactive about my brakes would most likely have stopped the whole thing happening in the first place.

Have been very interested reading all this discussion and will have to read it again to digest. In reference to Hack's levels I think I would be around "Beginner/Intermediate to intermediate".
This is THE take home message of this entire thread so far. This always seems to be the case - signs were there and not looked into thoroughly enough. We'll see what the failure was hopefully, maybe it'll turn out to be something random that wouldn't have given any clue even on visual inspection, we'll see. Someone mentioned that the car in my avatar had a brake failure to result in a multiple endo crash, and this is correct, and an example of how lucky the OP is. After the wreck, we were informed that the pedal had gone nearly to the floor earlier in the lap, but then pressure did normalize for subsequent turns until it was just suddenly gone at a very bad time (150+ at the end of a straightaway). The "moral" of the story here is that a normally functioning brake system will not do severely weird things without something substantial being wrong. Certain predictable things will happen as brakes wear during a session or race, but they are predictable. If anything happens that is out side of these predictable changes or sensations, the best thing is to have an abundance of caution and fully inspect the system; reckless abandon, assuming "oh, it'll be fine", can result in just barely skirting through a gate (best case scenario) or worse (total loss of a car)..... In a race, I can see trying to continue on because it's a race... In a non-racing situation, there is no legitimate reason to not stop, pull wheels and inspect the system if anything out of the ordinary happens.
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      02-01-2011, 02:18 PM   #40
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This is THE take home message of this entire thread so far. This always seems to be the case - signs were there and not looked into thoroughly enough. We'll see what the failure was hopefully, maybe it'll turn out to be something random that wouldn't have given any clue even on visual inspection, we'll see. Someone mentioned that the car in my avatar had a brake failure to result in a multiple endo crash, and this is correct, and an example of how lucky the OP is. After the wreck, we were informed that the pedal had gone nearly to the floor earlier in the lap, but then pressure did normalize for subsequent turns until it was just suddenly gone at a very bad time (150+ at the end of a straightaway). The "moral" of the story here is that a normally functioning brake system will not do severely weird things without something substantial being wrong. Certain predictable things will happen as brakes wear during a session or race, but they are predictable. If anything happens that is out side of these predictable changes or sensations, the best thing is to have an abundance of caution and fully inspect the system; reckless abandon, assuming "oh, it'll be fine", can result in just barely skirting through a gate (best case scenario) or worse (total loss of a car)..... In a race, I can see trying to continue on because it's a race... In a non-racing situation, there is no legitimate reason to not stop, pull wheels and inspect the system if anything out of the ordinary happens.
Noted. Will be on the lookout for these signs when I track for the first time ever in a few months
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      02-11-2011, 02:01 AM   #41
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Talking

Well she's back with her sister where she belongs, and more badass than ever! A few new paint chips....... but she got off so easy.... all I can do is grin.

Turns out the first part to melt and start spewing fluid was the piston seals on the stock brakes. Anyone want a pic of that, LMK (don't have it here right now). Anyway, it doesn't really say anything about the stock system. Something had to fail with the pads and rotors at such extreme temps while the pads were breaking down. I'm kindda glad it wasn't the seals in the brake lines though, since they are stoptech.

As for why the brake sensor didn't go off until later, my fantastic tuner's best guess is that the inner pad was destructing far more quickly than the outer pad where the sensor is located.

So far the new CL endurance pads seem fine for the street. I had to put them straight on the new rotors because I don't have time to bed in before tomorrow's track day, and sintered pads don't require (and don't have) a transfer layer. They are actually far, far less noisey than the Hawk HPS (not hard to do!!) and don't feel like you're grinding rings into the rotors every time you brake. Tomorrow will be the real test, but so long as they work well on the track they just might be the perfect pad.

And yes, I will be infinitely more careful today, tomorrow, and forever!

Thanks heaps to the boys at Southern BM for getting me back on track yet again. And to Dave Z for coming through with a phenomenal BBK.
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      02-11-2011, 07:52 AM   #42
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As for why the brake sensor didn't go off until later, my fantastic tuner's best guess is that the inner pad was destructing far more quickly than the outer pad where the sensor is located.
Actually, the inboard pad is the one that gets the sensor. I'm guessing it didn't got off because you had tapered wear. But hard to know from so far away.

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So far the new CL endurance pads seem fine for the street. I had to put them straight on the new rotors because I don't have time to bed in before tomorrow's track day, and sintered pads don't require (and don't have) a transfer layer. They are actually far, far less noisey than the Hawk HPS (not hard to do!!) and don't feel like you're grinding rings into the rotors every time you brake. Tomorrow will be the real test, but so long as they work well on the track they just might be the perfect pad.
That's what I was hoping when I installed them in the StopTech Trophy brakes on my Corvette. And for a short while, other than clicking in the calipers when they were cold, they really were silent. But then they started squealing like crazy on the street and, after my first track event with them, never stopped being noisy. While they behave well, performance wise, on the street, they simply drove me crazy. Maybe you'll get lucky, but I didn't.

One thing the CL RC6E pads did amazingly well is bite instantly in the rain. Because they are sintered metal and porous, there is absolutely no delay. Let me tell you, THAT takes some getting used to. I had to retrain my muscle memory when heel/toe downshifting to avoid overbraking.

Here's a shot of me at New Hampshire International Speedway testing out the CL pads in the rain:



Beautiful photos of your car, by the way! Glad you "landed" safely at that last track event and actually had a car left to install the new Trophy brakes on. I don't think you'll be melting your caliper piston seals any more.
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      02-11-2011, 07:17 PM   #43
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Turns out the first part to melt and start spewing fluid was the piston seals on the stock brakes. Anyone want a pic of that, LMK (don't have it here right now).
I mean, You would have to had so much fade for so long.... I just can't believe this.
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      02-12-2011, 01:53 AM   #44
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Thanks Dave! The whole package was truly awesome today. I was a little careful for the first couple of sessions, but after that I had to really change the way I drive her. It just seemed like endless brake into every corner lap after lap after lap. I know my brakes could have kept going long after my street tires were done.

My friend also put R6E's on his M3 last week for todays track day. His rattle heaps when cold, he says it sounds like a dump truck and his lady can hear him two blocks away. Also they seem to squeal more than mine, even when he was lapping I noticed them squealing lots on his vid. (what could this mean? seems unusual....)

But I have no rattle and no squeal after the first lap. I think once they have been left to sit they might not be so quiet on the street... we'll see. But in relation to the rattle I thought maybe they fit Stoptechs better than they fit the standard M3 system. I guess not if they were the same for you? He was still very happy with them though, and will switch back for the street anyway. For me, I think I'll wait and see how they go.
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