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      02-21-2014, 03:14 PM   #89
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Same here , except power shades cause I will tint heavily
Nice. I'm tinting heavily as we'll but I love rear shades with a sedan. Don't know why actually.
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      02-21-2014, 03:21 PM   #90
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Originally Posted by Tonymiabmw View Post
Same here , except power shades cause I will tint heavily
Nice. I'm tinting heavily as we'll but I love rear shades with a sedan. Don't know why actually.
My kids mess with them so I don't bother.
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      02-21-2014, 03:41 PM   #91
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My pops crashed his R8 didn't go up in flames but the airbags didn't go off. Audi tried to say that the angle he hit the front of the car that the airbags shouldn't have gone off hard to believe. Airbags should go off in any crash at 90mph
Audi's explanation is spot on. The airbags only go off if there is any g-forces in the direction the airbags are placed. In a head on collision the front airbags will go off, but not in a side- or rear collision. This is not by chance, but is based on loads of crashed cars and 1000's of hours of research and development. There are g-sensors and complex electronic systems that decide which airbags to activate.

What use is a airbag going off that is placed in the opposite direction of where the occupant is headed towards during the collision?
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      02-21-2014, 04:15 PM   #92
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Originally Posted by CanAutM3 View Post
It is not because that they are cooler when coming off track that they are cooler when in operation.

CCBs have better heat dissipation capabilities than cast irons, so they cool down faster (this is why they have better resistance to fade). But while in operation (during braking), they do run much hotter than cast iron ones.
Not quite. The primary reason CSiC brakes are more resistant to fade is because they are mated to a brake pad that is able to operate at higher temperatures. Fade, in any form, with any rotor is a pad phenomena, not a rotor phenomena.

Brake temperatures (rotor and pads) fluctuate (obviously) with the application of brake loads and the period in between when they are only cooling with no applied loads. Despite cooling better CSiC brakes also heat up more for a given brake load. If it were not for a matched pad designed to deal with these higher temperatures, this particular feature of a CSiC rotor (very light weight) actually makes them more fade prone. Again to be clear, not necessarily more fade prone than some base non CSiC system, but simply more fade prone than if they operated at a cooler peak/average temperature.
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      02-21-2014, 04:29 PM   #93
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Originally Posted by Brosef View Post
you have an awfully easy time justifying $8,150 for upgraded brakes (which in the opinion of most on here, are unnecessary and disadvantageous for long-term use) considering you also harp about how you don't see the M3 being worth it for an extra $12k over the price of an S4.

GFY. you're in no position to call the M3 owners on here cheap for not ticking the box on this option, for a multitude of reasons.
Bravo!
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      02-21-2014, 04:34 PM   #94
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Originally Posted by swamp2 View Post
Not quite. The primary reason CSiC brakes are more resistant to fade is because they are mated to a brake pad that is able to operate at higher temperatures. Fade, in any form, with any rotor is a pad phenomena, not a rotor phenomena.

Brake temperatures (rotor and pads) fluctuate (obviously) with the application of brake loads and the period in between when they are only cooling with no applied loads. Despite cooling better CSiC brakes also heat up more for a given brake load. If it were not for a matched pad designed to deal with these higher temperatures, this particular feature of a CSiC rotor (very light weight) actually makes them more fade prone. Again to be clear, not necessarily more fade prone than some base non CSiC system, but simply more fade prone than if they operated at a cooler peak/average temperature.
thank god finally someone who understands real reason for brake fade.. was about to loose hope in this forum.. buncha people needing to justify their reason to dump cash..
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      02-21-2014, 04:43 PM   #95
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thank god finally someone who understands real reason for brake fade.. was about to loose hope in this forum.. buncha people needing to justify their reason to dump cash..
Again, only one person is justifying their reason to dump cash. The rest of us are going the opposite route and saying that the stock brakes will suit us just fine.
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      02-21-2014, 04:44 PM   #96
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Quote:
Originally Posted by swamp2 View Post
Not quite. The primary reason CSiC brakes are more resistant to fade is because they are mated to a brake pad that is able to operate at higher temperatures. Fade, in any form, with any rotor is a pad phenomena, not a rotor phenomena.

Brake temperatures (rotor and pads) fluctuate (obviously) with the application of brake loads and the period in between when they are only cooling with no applied loads. Despite cooling better CSiC brakes also heat up more for a given brake load. If it were not for a matched pad designed to deal with these higher temperatures, this particular feature of a CSiC rotor (very light weight) actually makes them more fade prone. Again to be clear, not necessarily more fade prone than some base non CSiC system, but simply more fade prone than if they operated at a cooler peak/average temperature.
If you have a hot disc that stays hot until the next braking zone, wouldn't that extra heat retained in the disc transfer to the pad when the brakes are re-applied and cause the pad to fade?

I agree that fade originates from the pad and that CCBs can be fitted with much more aggresive pads. But the overall brake system's ability to dissipate heat during braking and between braking is also a big contributor to how the pads will be able to resist fade.

Anyway the point of my post was not about a dissection of why CCB perform better...

Last edited by CanAutM3; 02-21-2014 at 05:01 PM..
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      02-21-2014, 04:44 PM   #97
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Quote:
Originally Posted by swamp2
Quote:
Originally Posted by CanAutM3 View Post
It is not because that they are cooler when coming off track that they are cooler when in operation.

CCBs have better heat dissipation capabilities than cast irons, so they cool down faster (this is why they have better resistance to fade). But while in operation (during braking), they do run much hotter than cast iron ones.
Not quite. The primary reason CSiC brakes are more resistant to fade is because they are mated to a brake pad that is able to operate at higher temperatures. Fade, in any form, with any rotor is a pad phenomena, not a rotor phenomena.

Brake temperatures (rotor and pads) fluctuate (obviously) with the application of brake loads and the period in between when they are only cooling with no applied loads. Despite cooling better CSiC brakes also heat up more for a given brake load. If it were not for a matched pad designed to deal with these higher temperatures, this particular feature of a CSiC rotor (very light weight) actually makes them more fade prone. Again to be clear, not necessarily more fade prone than some base non CSiC system, but simply more fade prone than if they operated at a cooler peak/average temperature.
I'm not an expert on CSiC brakes, but isn't the reason they heat up more because the CSiC rotors can be matched with a much higher friction brake pad? Since the CSiC rotor have much harder surface and therefore less prone to wear they can also have a brake pad that has higher friction. Higher friction causes more heat obviously. The pads have a bonding material that is more heat resistant so fade is not an issue.

That's what I thought was both the reason for the high operating temperature and relative fade resistance. But is it correct...???
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      02-21-2014, 04:57 PM   #98
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So how many of you guys manage to keep the car longer than the warranty and modify your car, treat your car with your inner passionate instead of a DD tool with some tracking potential? If you are just gonna lease the car and return it then I agree this option is a totally waste of money. However for ppl who's going to modify the car, they gonna need the BBK sooner or later for another 8000, so why not take the chance to get it from stock plus you get the carbon ceramic rotors. Even if the rotors can not maintain long enough you could still get steel rotors for replacement like the after market BBK. Am I making any mistakes from this point of view?
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      02-21-2014, 04:59 PM   #99
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Can we at least agree that if it was a no cost option everyone posting here would take it? Literally if you had to check a box that said "Steel Brakes $0" or else you would get the CCB as standard equipment.
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      02-21-2014, 05:09 PM   #100
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Quote:
Originally Posted by gee-m-w View Post
Can we at least agree that if it was a no cost option everyone posting here would take it? Literally if you had to check a box that said "Steel Brakes $0" or else you would get the CCB as standard equipment.

Of course, but that isn't the case. Hell, even if the CCB's were half the price, more would be willing to opt for it. That doesn't change the debate regarding its performance relative to steel brakes however.
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      02-21-2014, 05:14 PM   #101
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Quote:
Originally Posted by Boss330 View Post
I'm not an expert on CSiC brakes, but isn't the reason they heat up more because the CSiC rotors can be matched with a much higher friction brake pad? Since the CSiC rotor have much harder surface and therefore less prone to wear they can also have a brake pad that has higher friction. Higher friction causes more heat obviously. The pads have a bonding material that is more heat resistant so fade is not an issue.

That's what I thought was both the reason for the high operating temperature and relative fade resistance. But is it correct...???
I am also no expert. I can only relay my layman view on this topic. As you stated, much more aggressive pads can be fitted to CCBs. However, all pads do reach their fade limit at some point. Since the CCBs operate hotter, this also means that even the more aggresive pads are operating closer to their fade limit. For example, if you were to install a CCB system on a rig with a powerful engine and run it non-stop with the brake applied (no cooldown), the heat will build up and the pads will fade at some point. But since the CCBs can dissipate heat very well, they get an efficient cooldown before every brake application.

IMO, it is really the whole system that contributes to the resistance to fade.

PS the little knowledge I have on CCB is on aircraft application, not cars.

Last edited by CanAutM3; 02-21-2014 at 05:22 PM..
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      02-21-2014, 05:16 PM   #102
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Quote:
Originally Posted by gee-m-w View Post
Can we at least agree that if it was a no cost option everyone posting here would take it? Literally if you had to check a box that said "Steel Brakes $0" or else you would get the CCB as standard equipment.
Most likely, even at a more reasonable price I would consider them.

I have always stated that not opting for CCBs is a cost/benefit decision for me.
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      02-21-2014, 05:18 PM   #103
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It's about $13,000 to do just the fronts.

http://www.bks-tuning.com/OEM-Euro-B...Carbon/Ceramic
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      02-21-2014, 05:24 PM   #104
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I have always stated that not opting for CCBs is a cost/benefit decision for me.
As it should be....and as it is for most of us.
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      02-21-2014, 05:24 PM   #105
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Quote:
Originally Posted by CanAutM3
Quote:
Originally Posted by Boss330 View Post
I'm not an expert on CSiC brakes, but isn't the reason they heat up more because the CSiC rotors can be matched with a much higher friction brake pad? Since the CSiC rotor have much harder surface and therefore less prone to wear they can also have a brake pad that has higher friction. Higher friction causes more heat obviously. The pads have a bonding material that is more heat resistant so fade is not an issue.

That's what I thought was both the reason for the high operating temperature and relative fade resistance. But is it correct...???
I am also no expert. I can only relay my layman view on this topic. As you stated, much more aggressive pads can be fitted to CCBs. However, all pads do reach their fade limit at some point. Since the CCBs operate hotter, this also means that even the more aggresive pads are operating closer to their fade limit. But since the CCBs can dissipate heat very well, they get a good cooldown before the next brake application. For example, if you were to install a CCB system on a rig with a powerful engine and run it non-stop with the brake applied (no cooldown), the heat will build up and the pads will fade at some point.

IMO, it is really the whole system that contributes to the resistance to fade.

PS the little knowledge I have on CCB is on aircraft application, not cars.
Sounds convincing
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      02-21-2014, 05:34 PM   #106
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My 8k is going into some BBS FI
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      02-21-2014, 06:45 PM   #107
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Quote:
Originally Posted by Tonymiabmw View Post
You must have a lot of free time to sit around and argue all day.


Quote:
Originally Posted by gee-m-w View Post
You guys should all write letters to BMW for offering such a stupid option. What are they doing to the brand offering high end motorsports parts? This is a street car. We need things like a tablet on the dash with a live dyno chart. Glowing LED seats. What if I want to hear electric car sound through the speakers? These are the options we should be talking about.

Clearly CCB are overkill for any and all use cases you can think of, from going to Target all the way up to cup racing.

For the old timers I'd like you to link some usenet posts where you all talked down disc brakes and "stuck with drums" because "that's how it was in the 70's" and "because BMW 2002i" and "Roundel said drums are easier to maintain".

I also find it completely illogical that on the one hand, 99% of owners treat their cars like garbage for 4 years and 50,000 miles and blame everything that goes wrong on BMW. You'll drive around with broken parts with 2 weeks waiting for a dealer appointment instead of just getting it fixed. But at the same time everyone is worried what will happen to these brakes at 100,000 miles. 70% of people will lease the car because the residuals are attractive, so they're out. 20% of the people will sell it before it has 50k miles. A few people who claim to keep an ultra high end luxury car for a decade (I've never met one) are worried that even though they rode the depreciation curve all the way down, that an expensive brake job is keeping them on the fence. I don't think anyone is serious or has given it much thought.

What most of you are trying to say is you can't get your head around an $8100 option. You're so put off by the price that you can't see the value. So you come up with reasons why it's a trick, or why it's bad technology, or what the 1999 Porsche Turbo guys are doing.
For $8,100, I'd rather have a Brembo 380mm kit or AP BBK and a set of TE37's with some Rival tires for the track, along a set of track pads for the BBK. Or just get the wheels/tires and pocket the rest for more track time. Or the TE37/Tires and some KW Clubsports?

Quote:
Originally Posted by gee-m-w View Post
Can we at least agree that if it was a no cost option everyone posting here would take it? Literally if you had to check a box that said "Steel Brakes $0" or else you would get the CCB as standard equipment.
That depends on how much the replacment cost of the CCB's is. From what I understand, the CCB rotor is larger than the steel rotor. Does anyone make a replacement steel rotor for the CCB yet?
There's definitely a bling factor with them, but they really don't interest me that much.

.
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Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."

Last edited by aus; 02-21-2014 at 07:22 PM..
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      02-21-2014, 07:09 PM   #108
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From my "foreign car" perspective one of the killer reasons to switch is access to 4 wheel CCB. I'm not necessarily getting more horsepower. I'm losing my hydraulic steering. I'll have to deal with efficient dynamics and start/stop. I'll have to pull some fuse to get rid of the engine sounds in the speakers.

I want to believe this brake kit is awesome. If it sucks this might not be a good car for me or provide no additional utility.
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      02-21-2014, 07:19 PM   #109
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Quote:
Originally Posted by gee-m-w
From my "foreign car" perspective one of the killer reasons to switch is access to 4 wheel CCB. I'm not necessarily getting more horsepower. I'm losing my hydraulic steering. I'll have to deal with efficient dynamics and start/stop. I'll have to pull some fuse to get rid of the engine sounds in the speakers.

I want to believe this brake kit is awesome. If it sucks this might not be a good car for me or provide no additional utility.
Omg this is such a troll statement, your gonna start a whole new round of argument over this one. Please no one respond to him.
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      02-22-2014, 12:14 AM   #110
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I thought these notes from a PFC race engineer I chatted with might be of interest, it's easy to misuse terminology when talking about brakes, most use the term "fade" generically, I certainly have before. (text in parenthesis are my notes on usual cause)


-Brake fade is when the pedal is hard, but after a period of time the braking efficiency starts to diminish. (pad temp issue)

-Brake compressibility is when the pedal starts to get spongy and and pumping the pedal doesn't help pedal firmness. (brake fluid temp issue)

-knock-back is when the pedal gets long and a tap of the pedal helps the pedal firmness (from hitting curbing, worn bearings, suspension issue, balance problem)

-ABS freeze is the brake pedal is hard, you apply more effort and no additional stopping power is available

-going over center on the brake pedal and loosing mechanical advantage, effect is soft pedal and lost efficiency.

-aggressive "jump in" from the initial apply and the ABS strategy implements a "preemptive mode" and pulls pressure out of the system there by reducing "bite" in an effort to maintain threshold tire grip,

Last edited by consolidated; 02-22-2014 at 12:20 AM..
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