[Rafichicago]

I haven't driven M5 with steel brakes. Mine has ceramics. That was the only thing I have difficulties to adjust to this day. Initial bite is instantaneous and quite hard to adjust unless you daily drive it. Honestly not even sure if there are any numbers that confirm if CCB's braking distance is shorter from steels. I'd say it probably differs since the kit is bigger. Not all 20" wheels clear CCB's Buying CCBs and spending $8K just to get of brake dust is plain lunacy in my book unless you use Benjamins for certain activity in the bathroom. Also some people will sacrifice initial bite for cleaner wheels swapping one brake pads for others but purchase car with huge emphasis on safety. Carbon ceramics for the road are overkill anyways. They're great to have but they come at pretty high cost. Not only initially but also when they need replacement. They're also much more prone to damages exactly why some will actually order their track cars without them. To each it's own I guess

[pbonsalb]

Initial bite has little to do with stopping distances but generally makes uninformed drivers think they have really good brakes. Not saying the M5 ceramics aren’t really good brakes — they are, but you won’t be able to measure any difference in stopping versus steel until both sets are very very hot. The kind of hot you won’t see in any normal street driving. You could see it in hardcore mountain or canyon driving, but generally it’s a track thing.

They are lighter and that is probably the performance benefit more drivers could feel since unsprung weight reduction is worth more than twice that of sprung weight reduction.

[jnotrom711]

Originally Posted by Rafichicago

I haven't driven M5 with steel brakes. Mine has ceramics. That was the only thing I have difficulties to adjust to this day. Initial bite is instantaneous and quite hard to adjust unless you daily drive it. Honestly not even sure if there are any numbers that confirm if CCB's braking distance is shorter from steels. I'd say it probably differs since the kit is bigger. Not all 20" wheels clear CCB's Buying CCBs and spending $8K just to get of brake dust is plain lunacy in my book unless you use Benjamins for certain activity in the bathroom. Also some people will sacrifice initial bite for cleaner wheels swapping one brake pads for others but purchase car with huge emphasis on safety. Carbon ceramics for the road are overkill anyways. They're great to have but they come at pretty high cost. Not only initially but also when they need replacement. They're also much more prone to damages exactly why some will actually order their track cars without them. To each it's own I guess

As an fyi, most may not know but the difference in size between the f90 CCB front rotor and steel front rotor is only 16 mm. Which equates to just over 1/2 inch total diameter. .25 radius.

Not 100% sure , but like 95% sure the front caliper is identical for steel vs ccb on the f90. I’ve seen conflicting information that a ccb rotor with ccb pads could fit just fine in the blue steel caliper. Not sure if there is a different mounting location or bracket to move the caliper out .25” for ccb. But the size difference it self is negligible. And if the mounting location is the same, any wheel that clears the steel brakes will also clear a ccb on the f90. Even if the mounting location is .25 further from the center of the hub, I would think still most wheels that clear the steel will also clear a ccb.

Could be mistaken but I believe even the 19” bmw f90 wheel can still clear the ccb.

[Rafichicago]

There's someone here trying to sell 20" bbs wheels stating clearly that they will not clear CCB brakes. That's how I came to that conclusion that there's size difference. I will tell you though that I have removed wheels couple of times. There is about 1/8th inch of the clearance between 20" 706M wheel barrel and caliper if not less so I don't see how 19s would clear that caliper. Maybe someone more knowledgeable would chime in to tell us 100%

[jnotrom711]

Originally Posted by Rafichicago

There's someone here trying to sell 20" bbs wheels stating clearly that they will not clear CCB brakes. That's how I came to that conclusion that there's size difference. I will tell you though that I have removed wheels couple of times. There is about 1/8th inch of the clearance between 20" 706M wheel barrel and caliper if not less so I don't see how 19s would clear that caliper. Maybe someone more knowledgeable would chime in to tell us 100%

Not sure,

I don't have CCB, I have steel, and 20" 789M wheels. But it appears you can spec an M5 with the standard 19"wheels and add the CCBs, with out having to change the wheels. I would think they would force you to choose a 20" option on bmwusa.com, if that was the case.

But like I said, i'm nearly positive the calipers are the exact same, just painted blue vs gold (with other options now for colors). And I haven't dug enough to see if the CCB option would require moving the calipers to fit the CCB rotors. IF they are the same calipers, and IF they mount in the same location, any wheel that fits over the steel will also fit over the CCB.

[pbonsalb]

ShawnHayes has test fitted steel rotors to CCB calipers. You can look up his posts on the subject. He is changing to steel rotors and aftermarket pads because he tracks the car and tracking is wearing out his expensive carbon rotors and pads. He would not be doing this if he thought breaking performance would suffer noticeably, but I am sure he will report after his first track day with the steel rotors. I am curious.

[aj_g80]

Originally Posted by pbonsalb

ShawnHayes has test fitted steel rotors to CCB calipers. You can look up his posts on the subject. He is changing to steel rotors and aftermarket pads because he tracks the car and tracking is wearing out his expensive carbon rotors and pads. He would not be doing this if he thought breaking performance would suffer noticeably, but I am sure he will report after his first track day with the steel rotors. I am curious.

Nobody here is a race car driver. Giving up a few feet here and there with steels vs ccb's doesn't matter. If Mclaren guys are swapping out ceramic to track with steels, why wouldn't a bmw driver do it? LOL

[AHall]

Originally Posted by aj_g80

Nobody here is a race car driver. Giving up a few feet here and there with steels vs ccb's doesn't matter. If Mclaren guys are swapping out ceramic to track with steels, why wouldn't a bmw driver do it? LOL

Why would the McLaren guys switch to steel brakes for track? If they are driving a 720 or whatever it is, cost could not be the reason, could it?

[aj_g80]

Originally Posted by AHall

Why would the McLaren guys switch to steel brakes for track? If they are driving a 720 or whatever it is, cost could not be the reason, could it?

No matter how much money you make, nobody is going to piss away money on rotors for a track day. Period.

[AHall]

Originally Posted by aj_g80

No matter how much money you make, nobody is going to piss away money on rotors for a track day. Period.

So what really is the point of CCB, other than reducing brake dust?

[aj_g80]

Originally Posted by AHall

So what really is the point of CCB, other than reducing brake dust?

dont ask me... LOL.

Very ironic given the CCB price tag you can't (shouldn't) track them...


prior to CS did i option them on my cars? Absolutely. I wash my own cars, and the 8k is worth not spending 20 minutes to clean each wheel. I'am by no means a high options person, but CCB is something i must have..

I've seen people say they can't have a car without Drivers assist.. to each their own..

[shawnhayes]

First off, the idea that carbons don't reduce braking distance is absolute bullshit. The weight reduction in the car ALONE makes a difference. Illustration:

5 meters, nothing? Really?

Shawn

[shawnhayes]

Originally Posted by pbonsalb

ShawnHayes has test fitted steel rotors to CCB calipers. You can look up his posts on the subject. He is changing to steel rotors and aftermarket pads because he tracks the car and tracking is wearing out his expensive carbon rotors and pads. He would not be doing this if he thought breaking performance would suffer noticeably, but I am sure he will report after his first track day with the steel rotors. I am curious.

Second point,

If I was RACING the CS for money? CCB, ALL DAY, EVERY DAY.

For trackdays? 5 meters? So what? If 5 meters makes the difference between you and wrecking, then you've done something wrong. Very wrong. There should always be something on the table for space.

So, please, CCB's DO make a difference. They DO. But they are VERY VERY expensive to replace. For a guy who tracks as often as I do, I'm taking them off and putting them in a corner while I use metals.

Vin Diesel comes out and challenges me? Even to a DRAG RACE - the CCB's go back on. The weight alone is worth it.

Shawn

[shawnhayes]

Originally Posted by jnotrom711

Not sure,

I don't have CCB, I have steel, and 20" 789M wheels. But it appears you can spec an M5 with the standard 19"wheels and add the CCBs, with out having to change the wheels. I would think they would force you to choose a 20" option on bmwusa.com, if that was the case.

But like I said, i'm nearly positive the calipers are the exact same, just painted blue vs gold (with other options now for colors). And I haven't dug enough to see if the CCB option would require moving the calipers to fit the CCB rotors. IF they are the same calipers, and IF they mount in the same location, any wheel that fits over the steel will also fit over the CCB.

The 19 inches do fit, they are just VERY close. Different wheels will not fit the CCB's, maybe BBS's on that list as well.

The CCB rotor/caliper IS bigger than the metals, but just a teensy weensy bit (its a few mm). The metals FIT the CCB caliper with the metal pad. The other consideration is HEAT. CCB's get HOT. I mean REAL HOT. The metals stay hotter longer, the CCB's dissipate it quickly, but the peak temps are much higher. Maybe the OEM's don't like the wheel barrel to be so close. I dunno.

Shawn

[shawnhayes]

Originally Posted by jnotrom711

But like I said, i'm nearly positive the calipers are the exact same, just painted blue vs gold (with other options now for colors). And I haven't dug enough to see if the CCB option would require moving the calipers to fit the CCB rotors. IF they are the same calipers, and IF they mount in the same location, any wheel that fits over the steel will also fit over the CCB.

They're not the same. The CCB rotor is a few mm bigger. The CCB caliper is a few mm further out from the hub, but it ain't MUCH.

Here's BMW stock F90 rotors in a CCB caliper (mine).



So, THIS will work for ME. I can use a metal rotor. I do not know if the reverse is true. Only way to know it is to try. Measurements only give you a close idea. The measurements told me what you're looking at would not work. It does, but only because BMW has wisely given MORE tolerance than needed with the pad/rotor placement in the pocket.

Shawn

[pbonsalb]

Originally Posted by shawnhayes

First off, the idea that carbons don't reduce braking distance is absolute bullshit. The weight reduction in the car ALONE makes a difference. Illustration:

5 meters, nothing? Really?

Shawn

I have not seen the test of the M5 with carbon brakes and an otherwise identical M5 with steel brakes in non-track testing (i.e., a single stop from 60-0 or 100-0). If there is 15’ difference, I would be surprised. The Porsche in the utube video does save 15’ from 80 mph, but I don’t know how the Porsche carbon brakes compare to their steel brakes.

[shawnhayes]

Originally Posted by pbonsalb

I have not seen the test of the M5 with carbon brakes and an otherwise identical M5 with steel brakes in non-track testing (i.e., a single stop from 60-0 or 100-0). If there is 15’ difference, I would be surprised.

I'm not going to do it myself either, but I can promise you there IS a difference. I don't know how big it is for one stop 60-0 or 100-0, but I promise there's SOME difference. At VIR, it equals 1 brake marker (100 ft) in starting the braking between my 2018 M5 and my 2022 M5 CS on the same tires. There are more variables there, but it made a pretty big difference. I pulled off about three seconds of 9/10ths effort there.

Shawn

[pbonsalb]

There is some discussion of the Porsche test here:

https://rennlist.com/forums/cayenne-...ference-5.html

Huge track difference between 2018 M5 and 2022 CS, but not sure how much can be attributed to carbon vs steel brakes. Weight, tires, suspension all play a role. But I definitely agree carbon brakes would help the most under track conditions.

[Neptune7]

I've owned M5s with both CCB and Steels and have not seen a difference in initial stopping power during occasional hard braking, though the CCBs seemed to be servoed to brake harder initially.

Here's an eg where two cars braked similarly with different brakes.

I do agree though that when doing journeys where repeated, frequent hard braking is required, and fade comes into play, the CCBs are more consistent and fade resistant.

[shawnhayes]

Originally Posted by Neptune7

I've owned M5s with both CCB and Steels and have not seen a difference in initial stopping power during occasional hard braking, though the CCBs seemed to be servoed to brake harder initially.

Here's an eg where two cars braked similarly with different brakes.

I do agree though that when doing journeys where repeated, frequent hard braking is required, and fade comes into play, the CCBs are more consistent and fade resistant.

8:41 - Matt says "the cars weigh the same, we've got the same brakes, and we stopped in the same distance".

Brakes LOOK different to me, but I can't tell for sure.

However, if BOTH metal and CCB's are overwhelming the tires and both are in ABS mode, it's the TIRES that limit the stopping distance. If the cars weigh the same, you could have F1 brakes on there, and if the tires are overwhelmed but equal both cars, physics says the braking distance has to be the same. That's a tire problem not a brake problem.

Shawn

[Neptune7]

Originally Posted by shawnhayes

8:41 - Matt says "the cars weigh the same, we've got the same brakes, and we stopped in the same distance".

Brakes LOOK different to me, but I can't tell for sure.

However, if BOTH metal and CCB's are overwhelming the tires and both are in ABS mode, it's the TIRES that limit the stopping distance. If the cars weigh the same, you could have F1 brakes on there, and if the tires are overwhelmed but equal both cars, physics says the braking distance has to be the same. That's a tire problem not a brake problem.

Shawn

Pretty sure Mat's mistaken. Those are the gold calipers on the M8.

And yes the tires do make a big difference.

One thing different is the pedal programming on the ccb's. The different "servo" is noticeable and the Harry's Garage video points it out too.

[shawnhayes]

Originally Posted by Neptune7

Pretty sure Mat's mistaken. Those are the gold calipers on the M8.

And yes the tires do make a big difference.

One thing different is the pedal programming on the ccb's. The different "servo" is noticeable and the Harry's Garage video points it out too.

Looked like the gold calipers to me too, but I think the P4S's equilibrated both cars to the exact same.

And I have to agree on the CCB's feel. Is it programming or the different master cylinder?

Shawn