CCB using a different brake booster

[karussell]

i seriously doubt any component of the ccb system other than the rotors and calipers are different. piston number and diameter is irrelevant. more pistons smaller diameter. i imagine they designed these components so there is minimal changes to other components. coefficient of friction on the brake surface is also going to be similar as the ccb specific brake pads are designed to work with them. tires far outgrip the brakes. tires stop the car. no point in making them over sensitive to brake input. something bmw knows very well. as touchy brakes equals unsmooth and unsmooth equals slow.

who cares if you track the car only once a year or even never. these are not track brakes. no matter what the marketing guys want you to think. you won't see one second difference in your lap time. just get them if you want to try them out and you think yellow looks better than blue. i will say its far cheaper to order them as an option than buying them after the fact. you get about a 50% discount compared to buying the rotors on their own.

buy em try em. like em keep em. if not, put them on shelf, get steels and enjoy. replace original ccb's when time to sell or sell them off and make a little cash when the unfortunate few decide to track them and end up in kitty litter and have tiny chip in them requiring axle set replacement at $16k or god forbid drop a track wheel on them when changing wheels.

[PABrian]

Originally Posted by karussell

i seriously doubt any component of the ccb system other than the rotors and calipers are different. piston number and diameter is irrelevant. more pistons smaller diameter. i imagine they designed these components so there is minimal changes to other components. coefficient of friction on the brake surface is also going to be similar as the ccb specific brake pads are designed to work with them. tires far outgrip the brakes. tires stop the car. no point in making them over sensitive to brake input. something bmw knows very well. as touchy brakes equals unsmooth and unsmooth equals slow.

who cares if you track the car only once a year or even never. these are not track brakes. no matter what the marketing guys want you to think. you won't see one second difference in your lap time. just get them if you want to try them out and you think yellow looks better than blue. i will say its far cheaper to order them as an option than buying them after the fact. you get about a 50% discount compared to buying the rotors on their own.

buy em try em. like em keep em. if not, put them on shelf, get steels and enjoy. replace original ccb's when time to sell or sell them off and make a little cash when the unfortunate few decide to track them and end up in kitty litter and have tiny chip in them requiring axle set replacement at $16k or god forbid drop a track wheel on them when changing wheels.

I guess you didn't read any of this thread or actually look into much of the information you're mentioning here.

1) Yes, more than just the rotors/pads changes when you get the CCB option. The brake booster is entirely different. Aside from that, yes they have made the system to be easily swapped. Pads, rotors, and brake booster.

2) Piston number and diameter IS, in fact relevant. On the M5/6, the calipers are the same, but the M3/4 get larger calipers when optioned with the CCB, meaning bigger pads and more friction surface. It's not going to lop 10 seconds off your lap times, but it's not irrelevant to everybody.

3) Tires far outgrip brakes? Since when? Ever hear of engaging ABS when it's dry and warm out? That, by definition, means it's the brakes that far outgrip the tires, and that's much preferable to it being the other way around.

4) The brake booster is different to help compensate for the (definite) change in coefficient of friction between the two systems, meaning you CAN have a better number and not have very touchy brakes. Have you driven a BMW with CCBs? I have...they're not too touchy at all for daily driving, but you can feel a difference when you get into them.

5) If you read earlier in this thread, you'd see some pricing information. It's $9,250 for CCBs on an M5/6, and as I mentioned earlier, a FULL set of rotors and pads, at list price, would run you about $12.5k...not $16k for an axle set of rotors, as you proposed. CCBs on the M3/4 will be slightly cheaper, at $8,150, meaning a full set of rotors and pads might be closer to the $10-11k range.

[karussell]

what i mean about brake systems is they are capable of getting tires to lock up. since the tires are doing the actual stopping there is no need to engineer a higher coefficient of friction in them relative to using a steel on steel, steel on carbon, hybrid on hybrid, versus a carbon on carbon friction surface. getting the balance just right and consistent is the devil in the details.

thats news to me the brake system is at all different. i said i highly doubt it.

i have driven an M5 with the ccb's. no discernable difference from the steel brakes. years of experience with porsches using the same manufacturer as everyone else for these ceramics.

this is all been debated up and down with the 996, 997 gt3's. the first generation 997 gt3's used a smaller diameter rotor on steels versus their ceramic atlernative. without any change to the brakes other than switching to the cup car steel rotors and shaving the pads down a bit there is not trouble with the rest of the components and braking performance is same.

but yes no one knows the story on the M4/M3 yet with these brakes. maybe they wanted to make the ceramics seem better by making them feel more grabby. hope not.

still the ceramics are great eye candy. not much else. save your money for more tires and brake pads with the steels.

[richardg]

The more and more I think about it the more I will likely skip the CCB

I know I don't need them and the thought process is 80% bling and 20% weight savings. The heat dissipation increase ultimately isn't anything that will affect me with my few track days yearly and low skills.

[Boss330]

Originally Posted by karussell

what i mean about brake systems is they are capable of getting tires to lock up. since the tires are doing the actual stopping there is no need to engineer a higher coefficient of friction in them relative to using a steel on steel, steel on carbon, hybrid on hybrid, versus a carbon on carbon friction surface. getting the balance just right and consistent is the devil in the details.

thats news to me the brake system is at all different. i said i highly doubt it.

i have driven an M5 with the ccb's. no discernable difference from the steel brakes. years of experience with porsches using the same manufacturer as everyone else for these ceramics.

this is all been debated up and down with the 996, 997 gt3's. the first generation 997 gt3's used a smaller diameter rotor on steels versus their ceramic atlernative. without any change to the brakes other than switching to the cup car steel rotors and shaving the pads down a bit there is not trouble with the rest of the components and braking performance is same.

but yes no one knows the story on the M4/M3 yet with these brakes. maybe they wanted to make the ceramics seem better by making them feel more grabby. hope not.

still the ceramics are great eye candy. not much else. save your money for more tires and brake pads with the steels.

I recommend reading the BMW Technical Training manual on CCB, found in this thread:

http://f10.m5post.com/forums/showthread.php?t=821498

The braking effect in a warm state could be considerably higher, but will be roughly the same as the M Compound brake system, as it is restricted by the adhesion of the tires.

5.3. Brake Booster
The brake booster is specifically designed for the increased coefficient of friction of the M Carbon ceramic brake. This is why it has its own part number. Without this adaptation, the behavior of the M Carbon ceramic brakes would be rated as disproportionately aggressive.

So, yes the CCB actually HAS a higher coefficient of friction than steel brakes and could have a "considerably" higher braking performance than the steel brakes if not limited by the tires, and it has a different brake booster so the driver feels the brakes performs as he would expect.

From what I have found the Porsche 997 has a different master cylinder as well between steel and CCB:

Steel part # 997 355 910 00
CCB part # 997 355 910 10

But as has been mentioned previously on this thread, it's not impossible to upgrade to different brake calipers without changing the master cylinder in an aftermarket application. But Porsche seemingly has found it necessary to have different master cylinders to achieve the desired brake pedal travel.

[karussell]

i saw that before. real world seat of the pants feel on 996, 997.1, 997.2 with ccb and ccb swapped to irons on track. no difference. pedal feel is same. at least to me. we have some people that swear up and down they feel different being the ccb's worked worse. now with abs there is likely a different map for the brake systems. what i will warn anyone trying this car with ccb's on track with R compound tires or slicks is to be cautious. if you look up abs ice mode with the gt3's this is something i'm particularly worried about manifesting itself on the new cars. switching to more aggressive tires up to full slicks could cause the abs system to freak out under certain conditions. would be great if someone had more insite if there is an ice mode and guidance on running something other than street tires.

[Boss330]

Originally Posted by karussell

i saw that before. real world seat of the pants feel on 996, 997.1, 997.2 with ccb and ccb swapped to irons on track. no difference. pedal feel is same. at least to me. we have some people that swear up and down they feel different being the ccb's worked worse. now with abs there is likely a different map for the brake systems. what i will warn anyone trying this car with ccb's on track with R compound tires or slicks is to be cautious. if you look up abs ice mode with the gt3's this is something i'm particularly worried about manifesting itself on the new cars. switching to more aggressive tires up to full slicks could cause the abs system to freak out under certain conditions. would be great if someone had more insite if there is an ice mode and guidance on running something other than street tires.

If you saw that before I don't understand why you "seriously doubted" there was any difference in parts such as the brake booster between the steel and CCB versions? It's clearly stated in the manual

The same also about the higher friction coefficient

[karussell]

the document is for the m5/m6 for one. for another that manual is a service technical bulletin so bmw technicians know they are different, how to check their condition, and service them. it does not go into detail the parts that are different. i still seriously doubt the m3/m4's components are different. and if they are a different part number i still think they don't vary by much. its a guess at this point. i haven't seen an official spec for the ccb's. although haven't looked either as they are useless anyways.

[PABrian]

Originally Posted by karussell

the document is for the m5/m6 for one. for another that manual is a service technical bulletin so bmw technicians know they are different, how to check their condition, and service them. it does not go into detail the parts that are different. i still seriously doubt the m3/m4's components are different. and if they are a different part number i still think they don't vary by much. its a guess at this point. i haven't seen an official spec for the ccb's. although haven't looked either as they are useless anyways.

Did you read that document? It actually does go into detail which parts are different and in what ways.

With the M3/4, it's also been established that the stock brakes feature four-pot front calipers and two-pot rears, while the CCBs have six-pot front calipers and four-pot rears (this is why there is a much greater weight advantage going to the CCBs on an M5/6 than on the M3/4). It would be entirely reasonable to assume that the brake booster will also be different between the two, but that hasn't been confirmed 100% yet.

[Boss330]

Originally Posted by karussell

it does not go into detail the parts that are different.

There aren't drawings and such going into minute details, but there is a separate chapter dealing with the differences/similaities between the CCB and steel brakes...

-Front calipers are different part number but only difference is mounting flange thickness
-Rear calipers are identical
-Brake pads are different and thinner because of thicker rotors
-Brake booster is different

And it clearly states the brake booster isn't just a different part number, but actually has different characteristics.

Not sure how you missed that part...

[karussell]

Originally Posted by OttosBMWBrian

Did you read that document? It actually does go into detail which parts are different and in what ways.

With the M3/4, it's also been established that the stock brakes feature four-pot front calipers and two-pot rears, while the CCBs have six-pot front calipers and four-pot rears (this is why there is a much greater weight advantage going to the CCBs on an M5/6 than on the M3/4). It would be entirely reasonable to assume that the brake booster will also be different between the two, but that hasn't been confirmed 100% yet.

exactly, so its just speculation on your part. the M5 and M6 are very heavy cars. even so i don't think the brake booster is very different. on the M3/M4 being much lighter i still don't think they will have different components. if the booster is a different part number i'm guessing the change is so minor that you couldn't tell the difference swapping out the ceramics for steel rotors and its certainly not something that would cost them more to change otherwise they would have solved it with different friction coefficient brake pads.

[FTS]

Originally Posted by karussell

would be great if someone had more insite if there is an ice mode and guidance on running something other than street tires.

The explanation on why ice mode happens is here:

[robbo mcs]

Hi,

Just to put some facts out there, rather than speculation.

The brake boosters are clearly different for the carbon ceramic and steel on the M4

Part number for carbon ceramic 34337850999
Part number for steel 34337849876

http://realoem.com/bmw/showparts.do?...06&hg=34&fg=27

The master cylinder is the same part number for both, 34337849878

http://realoem.com/bmw/showparts.do?...05&hg=34&fg=25

[Holset]

Originally Posted by FTS

The explanation on why ice mode happens is here:

Great video thanks for posting!