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      11-21-2014, 09:59 AM   #1
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Carbon Ceramics @ the Track

I'm curious if anyone with carbon ceramics has tracked or is planning to track their car?

I know the rotors are prohibitively expensive to replace but I would think that steel replacements might become available by the time you wear the stock-carbons out. Then I'm also curious how much faster they will wear out with light track use 3-4 times per year.
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      11-21-2014, 10:23 AM   #2
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M5 rear steel rotors should fit the fronts as replacement, and M3/4 front steels would be replacements for the rear ceramics

Also this topic is covered somewhat here: http://f80.bimmerpost.com/forums/sho....php?t=1047585
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      11-21-2014, 10:49 AM   #3
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Quote:
Originally Posted by FTS View Post
M5 rear steel rotors should fit the fronts as replacement, and M3/4 front steels would be replacements for the rear ceramics

Also this topic is covered somewhat here: http://f80.bimmerpost.com/forums/sho....php?t=1047585
Good info in that thread, thanks for the link. Also, good to know that steel replacements may in fact already be available. It's an interesting option to me if the carbon rotors might last for 3-4 years with light track use and then you at least have the option of cheaper steel replacements. You would still have the benefit of greater heat dissipation from the larger-than-standard calipers and rotors even if you switched to steel.

Also, I didn't realize that the master cylinder and brake booster were upgraded in addition to the calipers and correspondingly increased rotor sizes, another nice benefit from checking this option.
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      11-21-2014, 12:02 PM   #4
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Quote:
Originally Posted by ///Mobbin View Post
Good info in that thread, thanks for the link. Also, good to know that steel replacements may in fact already be available. It's an interesting option to me if the carbon rotors might last for 3-4 years with light track use and then you at least have the option of cheaper steel replacements. You would still have the benefit of greater heat dissipation from the larger-than-standard calipers and rotors even if you switched to steel.

Also, I didn't realize that the master cylinder and brake booster were upgraded in addition to the calipers and correspondingly increased rotor sizes, another nice benefit from checking this option.
I do not know for a fact that the master cylinder is upgraded, I think it is actually the same; however, booster is different. I am with you that the biggest benefit of the ceramics are the calipers and the booster, rotors in a sense are icing on the cake since they are consumables.

In terms of longevity on the track, my personal expectation is twice the life of steels. And if actually BMW honors free replacements as part of maintenance, even only once, the price they charge for the CCBs are justified for me. If they don't replace them, then I'll go with steel replacements.

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      11-21-2014, 01:39 PM   #5
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Quote:
Originally Posted by ///Mobbin View Post
Good info in that thread, thanks for the link. Also, good to know that steel replacements may in fact already be available. It's an interesting option to me if the carbon rotors might last for 3-4 years with light track use and then you at least have the option of cheaper steel replacements. You would still have the benefit of greater heat dissipation from the larger-than-standard calipers and rotors even if you switched to steel.

Also, I didn't realize that the master cylinder and brake booster were upgraded in addition to the calipers and correspondingly increased rotor sizes, another nice benefit from checking this option.
Quote:
Originally Posted by FTS View Post
I do not know for a fact that the master cylinder is upgraded, I think it is actually the same; however, booster is different. I am with you that the biggest benefit of the ceramics are the calipers and the booster, rotors in a sense are icing on the cake since they are consumables.

In terms of longevity on the track, my personal expectation is twice the life of steels. And if actually BMW honors free replacements as part of maintenance, even only once, the price they charge for the CCBs are justified for me. If they don't replace them, then I'll go with steel replacements.

Different is likely to be the most accepted way of describing the brake booster for the CCBs, due to the longer pad length and greater pad track acting at a slightly longer radius and greater force applied due to the extra pistons but mainly the greater friction coefficient of the CCB compounds, the mechanical advantage provided by the brake booster has been reduced to avoid having an overly aggressive brake characteristic.

Should you change to steel rotors the pad/disc size and piston advantages will still be present over stock brakes, with the added disadvantage of increased rotating mass over even the standard M-compound braking set up.
The advantage of the increased friction coefficient will be lost and although it will still be possible to exert sufficient force to lock wheels, due to the reduced mechanical advantage provided by the brake booster additional force will be required at the pedal.

How this would feel as compared to the stock steel set up I am unsure (less booster but more rotor/pad) but compared to the CCB set up this would feel significantly softer.
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      11-21-2014, 01:43 PM   #6
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I hadn't thought about that, you may be right. I am quite anxious to find out
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      11-21-2014, 04:18 PM   #7
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If you really mean light track useage and if you do not allow the pads to get more than 2/3rds worn before replacement, I think you will see far greater life of the CCB rotors than twice that of the steels.
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      11-21-2014, 08:12 PM   #8
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I am not sure what light track usage means. Is it # of days or driving non-agressively while on it? I do about 6-8 events a year, that's 16 to 24 days, but I am a light braker in general.

Also why change of pads so early be a good idea, how does it relate to the rotor's usage?

TIA.
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      11-22-2014, 10:42 AM   #9
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Quote:
Originally Posted by FTS View Post

Also why change of pads so early be a good idea, how does it relate to the rotor's usage?

TIA.
I can't find the link now, but there is something related to how the CCM materials are layered that causes the wear to accelerate significantly once the pads are beyond 50%. From what I remember, this is a pretty important factor, but I'd guess that most people will ignore it and bitch that their CCB's are trashed after 2 track days.
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      11-22-2014, 10:46 AM   #10
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Quote:
Originally Posted by Racer20 View Post
I can't find the link now, but there is something related to how the CCM materials are layered that causes the wear to accelerate significantly once the pads are beyond 50%. From what I remember, this is a pretty important factor, but I'd guess that most people will ignore it and bitch that their CCB's are trashed after 2 track days.
Could it simply be because when there is less pad thickness, there is less material to absorb heat and hence a higher surface temperature?

The same is seen on standard iron rotors, the more the pads are worn, the more sensitive a brake system is to fade and the faster the pads wear.
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      11-22-2014, 10:47 AM   #11
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Quote:
Originally Posted by FTS View Post
I am not sure what light track usage means. Is it # of days or driving non-agressively while on it? I do about 6-8 events a year, that's 16 to 24 days, but I am a light braker in general.

Also why change of pads so early be a good idea, how does it relate to the rotor's usage?

TIA.
You want to avoid any chance of getting close to the rivets that secure the pad to the backing plate as that will destroy the rotor. Also, the thinner the pad material the higher the heat radiated to the rotor, again increasing wear. Therefore, never start a session with well worn pads. On the Brembo CCBs on the ZR1, there are aggressive track drivers who have managed to keep the CCBs for years by always changing the pads when they are down to 1/3rd of the thickness. I have also seen this mentioned with the Porsche crowd when tracking with the CCBs, but some owners even mention replacing the pads at 1/2th thickness prior to a session. This may seem overkill to someone, but pads are extremely cheap compared to a CCM rotor particularly for the Porsche and BMW owners; (the rotors are much cheaper for the ZR1 even though damn near identical).

A "non-aggressive" HPDE driver would be someone who is perhaps in the intermediate group and is a 'light' braker IMHO.

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      11-22-2014, 10:54 AM   #12
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Originally Posted by thebishman View Post
A "non-aggressive" HPDE driver would be someone who is perhaps in the intermediate group and is a 'light' braker IMHO.
As a tidbit, I usually find that the intermediate/advanced students are the ones that are the toughest on their brakes. They have gained sufficient confidence to become decently quick, but tend to overbrake every corner .
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      11-22-2014, 04:21 PM   #13
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Quote:
Originally Posted by CanAutM3 View Post
As a tidbit, I usually find that the intermediate/advanced students are the ones that are the toughest on their brakes. They have gained sufficient confidence to become decently quick, but tend to overbrake every corner .
Well you're probably correct as I've been a not too aggressive braker in the advanced group for over 20 years. Hence its been a while since I was in the other groups.
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      11-22-2014, 07:37 PM   #14
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Quote:
Originally Posted by Racer20 View Post
I can't find the link now, but there is something related to how the CCM materials are layered that causes the wear to accelerate significantly once the pads are beyond 50%. From what I remember, this is a pretty important factor, but I'd guess that most people will ignore it and bitch that their CCB's are trashed after 2 track days.
Thank you, it would be great if you come across that link, we have quite a bit to learn. I'll keep it to 50% wear at most until we know more.

Quote:
Originally Posted by thebishman View Post
You want to avoid any chance of getting close to the rivets that secure the pad to the backing plate as that will destroy the rotor. Also, the thinner the pad material the higher the heat radiated to the rotor, again increasing wear. Therefore, never start a session with well worn pads. On the Brembo CCBs on the ZR1, there are aggressive track drivers who have managed to keep the CCBs for years by always changing the pads when they are down to 1/3rd of the thickness. I have also seen this mentioned with the Porsche crowd when tracking with the CCBs, but some owners even mention replacing the pads at 1/2th thickness prior to a session. This may seem overkill to someone, but pads are extremely cheap compared to a CCM rotor particularly for the Porsche and BMW owners; (the rotors are much cheaper for the ZR1 even though damn near identical).

A "non-aggressive" HPDE driver would be someone who is perhaps in the intermediate group and is a 'light' braker IMHO.

Bish
I guess it makes some sense, except that heat transfer should happen through the path of least physical resistance, so I would assume that heat would actually go towards the calipers and then to the fluid. But heat transference and thermal capacity of various materials (pads, rotors, calipers, etc.) is where I have least knowledge. Thank you for the input.

Quote:
Originally Posted by CanAutM3 View Post
As a tidbit, I usually find that the intermediate/advanced students are the ones that are the toughest on their brakes. They have gained sufficient confidence to become decently quick, but tend to overbrake every corner .
I agree as my experience has been similar.
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