[Musashi]

Hello

Starting this thread to see if there is an interest in custom-made 3d Carbon Ceramic brakes (CCBs) for our F3x type M Performance type series/chassis. This is not another thread regarding CCBs. Because the topic is not about CCBs but 3d CCBs, the long awaited CCB replacement, with patents owned only by 3-4 manufacturers. Brembo, for example, has not bought into these patents, they still produce the same 1980s chopped CCB we see on so many cars. The topic is also not about steel vs CCB vs 3d CCB track or street use, but the viability of 3d CCB as a lower cost vs Brembo/Stop Tech/Dinan steel sets, at equal performance but multi-fold longevity in actual day to day use.

Have been searching this topic for many years, spurred by the darn corrosive effects of winters on even the priciest carbon steel rotors. Ditched Japanese cars for rotting through by 5th year. By 2010, resolved rotor corrosion with Cadmium plating, resulting in unlimited corrosion resistance. No more edge peeling, center rusting, just surface wear. But Cad plating, rare this days as it is toxic, needs an untreated surface and it is incompatible with Zinc coated disks e.g. Brembo. Each week of cold slippery winter driving, the corrosion related rotor decay and preventive maintenance is the only performance nuisance I find with the Bavarian. I love the feeling of a perfect response brake pedal, rapid deceleration without pulsations or squeal. Was aware of CCBs as problematic for many reasons, and, until recently, never heard of CCB alternatives to our F30 chassis, let alone 3d CCBs. CCBs have been a long recurring discussion on Porsche, Audi, Ferrari, BMW related forums, esp the F8x type cars, as well as people seeking alternatives to cast iron discs. But mainstream 3 series had no alternative, and you could not fit after-market CCBs inside the 3 series while preserving stock specs - until now.

What is 3d CCB? "Next-generation technology that interweaves continuous carbon fibre to form a 3D multi-directional matrix which has significant benefits over traditional carbon-ceramic products" such as the chopped carbon-ceramic discs you find on production road cars. Source: https://surfacetransforms.com/white-...ramic-material 3d CCBs are similar among manufacturers, e.g. Fusion or ST 3d CCB brakes. However, two of the four 3d CCB manufacturers target the saturated Porsche, Lambo, Audi or Maserati market, and not the sub-400 mm market such as our Bavarians. ST released its brakes to the (Lambo/Porsche Gt) public in 2006. Two years ago Fusion announced mass producing 3d CCBs for a variety of cars, including BMW, but they remained focused on Lambo/Audi/Porsche.

A few months ago i interacted with one of the four manufacturers headed to the Dubai Auto Show. They sell for street and racing applications in Europe and Asia and North America is next. According to the maker, production broke mainstream, doubling since 2016, from 3,000 to 6,000 full sets or 24,000 3d CCB discs. Customers tend to be industrial clients, SUV / LandRover types fed up with frequent 1,700USD replacements, and performance car owners limited to sub-400mms front disks, where Brembo exclusivity starts.

3D CCB Characteristics:

- 70% less weight than cast iron discs; unsprung weight reduction equivalent x5
- acceleration, handling and cornering improvements, likely not noticeable at normal street speeds
- 30% reduction in stopping distance (TBD testing vs the 370mm M Perf)
- Excellent response below -40C/F, 0C and up to 1750 Celsius
- Work well wet or dry, high & low speed
- Rustless, dustless and noiseless (bedding plays a role)
- Rated 300,000 Kms spirited driving and occasional track use
- Compatible with Pagid RSC pads
- Compatible with original caliper system
- Does not degrade as fast as CCBs in cold temp/short brake cycles, CCBs operating best in a high Temperature range and long braking cycle
- Custom diameter and thickness
- Can be surfaced several times if frequently tracked


Material:

- Japanese T-700 carbon grade, used in aerospace, cars and pro bicycles.
- 3D, Continuous carbon fiber needled and inter-woven
- Density of 1.8-2.1g/cm3
- COF = 0.47-0.51 with stable CTE (2.6) operating temperature range below 0C/32F and above 1750C / 3182F or
- Not affected by oil spill like the resin pressed, chopped CCBs (e.g. Brembo)
- Production cycle: from 60 days now approx. 25-30 days, decreasing + shipping time.

Disadvantages

- High initial cost
- Not yet mainstream with known distributors
- Wait time (40 days) until distribution stores common sizes
- They have a rough, coarse look even when polished vs the granular looking CCBs A subjective thing.

Difference 3d CCB vs chopped/resin pressed CCBs e.g. Brembo

Most C-SiC brakes out there are compressed chopped carbon fibers with resin which releases bubbles/gas at elevated temperature. As a result, COF decreases and heat fading increases in track applications. Chopped resin pressed CCBs also require heat for responsiveness, offering minor if no performance improvement vs steel Brembo/M Performance type discs at normal, cooler street temperatures. Another issue encountered, some chopped CCBs are extremely vulnerable to an accidental oil spill on the rotor. Once the oil enters the resin, it delaminates the fibers and it needs replacement.

3d CCB, continuous carbon ceramic fiber is 3D needled and inter-woven to guarantee structural stability, hence their recurrence in racing application and do not suffer some of the limitations described above.

Testing : All manufacturers have tested them on various supercars and Formula chassis, as well on GT tracks. Users report good performance as low as -40C/F- according to manufacturers.

Price: sub 5,000$ for a 370-400mm type front rotor. Note that various performance offers of high grade cast rotors at Turner Motorsport / Dinan are similarly priced. Yet, as cast iron sets they will last some 80,000-100,000 kms down south, not here. If x3-5 high grade cast iron sets equate a single 3d CCB set, then this is a bargain.

Some users, especially whom drive spiritedly and occasionally track may benefit from such a product, as well as those irked by corrosion issues and salt issues in cold or coastal climates. Even those leasing, if migrating to a similar model, they can just move their 3d CCBs and return the car with stock. For heavy track users, a separate track-day steel set and brake fluid is perhaps a smarter alternative, and there are separate forum arguing that very well.

The reason why Canada never had the 4 year/free maintenance/rotors like the US or Australia is winter. BMW does not want to replace 1 or 2 sets and it is smart. Canadian winter roads get 9 million tons of salt, 24% salinity concentration (x2 sea), and an Atmospheric/Liquid Corrosion of 3000 percent vs a place like Central US. That means 1000 - 2500 μm steel wear / year or 1-3 mm. Because heavy winters are 4 months only, takes two winters for that. In addition, sub 0F cold prevents mechanical full pad adherence creating circular ring TV. Takes 2 winters, 6,000 salt exposure hours to eat your average good grade Brembo CCB before the mechanic recommends replacement. Note that lesser grade steel rotors rot faster so fail as low as one summer/winter 20,000 miles. With constant washing and almost futile efforts to bed them in Dec - mid March (impossible at -15F), my 370mm M Perf Brembos lasted 100,000 kms, 2 winters, and 4 summers. The average BBK owner probably spends 6-8k CAD in steel rotors over 300,000 kms (even if swapping cars, cost is included), and 100,000kms of these are poor quality braking kms - 25k x 4 or x5sets end of life rotor performance- less feedback, sagittal rust effects, squealing and TV etc. Again, this is a typical nordic snowbelt issue, excluding Toronto or Vancouver.

This begs the question, is the new 3d CCB tech the best solution in hotter climates? The old CCB, many disadvantages. But topic is not about CCBs, they are the 1980s past.

[kern417]

Doesn't seem worth it, even from the factory. I don't see anyone overwhelming some good slotted vented rotors, or even the stock blanks with some high performance pads. Yeah the specs show it's better but it's overkill for a street car.

[Musashi]

Feb dealership lot M Perfbrake vs bedded in/track brake.

[kern417]

Originally Posted by Musashi

When first picking up my car, an April, the rotors were in iffy outside winter storage shape. Needed multiple bed-in to fix it. After that, from 0 to -40C, 20F to -40F, it has been a struggle. At low temperatures, the car slides even with the best winter tyres- on dry asphalt. I need a -5 to +5 Celsius day to clean them up braking- and that means weeks waiting. They are too big to engage heat and clean, my customized Civic 300mms never had this issue and they were tiny. Managed to snag 100,000 kms for the 370s front but with lots of iffy moments. However, seen people change their M Perf after two winters, as low as 50k- Thickness Variation from winter ruts and not going out of their way to brake them. 50k= 6 front sets or 7000-8000$ in 300,000 kms with an iffy end of life is usually pulsating and problematic. Almost lost a set when, gone two weeks, my friend forgot to drive the car after several days of side-rain- an instruction he agreed with. needed several red hot cycles to fix it (see pic).

So far, as far as Sweden and Russia, winter driven CCBs have had zero returns and no rust. No grooving. Is it possible that makes it the best un-obvious bang per buck? Stopping distance is 10-20% better, no more, but they just last. No lip no ruts no rust.

That really doesn't make any sense. Ceramic brakes, by design, have worse performance than steel brakes when cold. It usually takes a few stops before they reach their optimal temp. The primary benefit is they hold up better to track duty, but steel brakes perform fine in that aspect as well. Ask Brembo, Wilwood, AP Racing, etc.

If you had that many issues with your stock brakes then something else was wrong. You said yourself that they were in iffy shape when you picked them up. And if your car is sliding when braking, that means 1. that your brakes overpowered your tires, and 2. your ABS didn't kick in. So again, pointing at an issue that isn't brake-related. It shouldn't be a surprise that you stock brakes can create more friction than what is between your winter tires and a cold road surface. I can make the ABS kick in on summer tires in warm weather if I hit the brakes hard enough.

Personally, I don't see any issue with the pic you posted. My brakes look like that any time it rains, and a few stops cleans it up. It's just surface rust, unless I'm missing another detail in the picture?

Regardless, bigger/ceramic rotors would only make your experience worse.

[F32Fleet]

Interesting. CCB's seem pointless on a daily driver with replacement costs being so hihh.

[Musashi]

bedded, rusting vs two competing 3D continuous...

[Musashi]

Originally Posted by F32Fleet

Interesting. CCB's seem pointless on a daily driver with replacement costs being so hihh.

4-5 months of the year steels are nearly useless and cold, squealing and pads not even touching the surface. After a few brembo sets lost to the elements or storage, feels good having a cheaper and superior alternative.

[F32Fleet]

Originally Posted by Musashi

You are correct- at that 300,000 kms shot. But oversized cast iron rotors cost us more up north than CCBs. M Perf here are some 1000$ plus labour so 1400$. Seen owners loose a set a winter because the top 1-2" of the disc never contacts the pad for weeks at a time, while being fully salted, cooled then heated in garage, so they rot 100 times faster than in rain. Most oversized Brembos last 2 winters so 50k (far costlier than the new CCBs). Those keeping cars a long time will outspend a CCB while having problematic squealing, pulsating or grinding every alternate winter. Our second 328i BMW, standard 320mm front Zimmerman rotors, (girl driven) are done after her first winter and she drags them to a second winter. 800$ per shot. In her case she just does not brake them enough.

In the lower 48 states winter temps are such that people can occasionally rinse off their vehicles and govts use a limited amount of corossive(sp?) "salt" on the roads.

Nobody goes through rotors because of corrosion. It just doesn't happen.


While the net cost of CCB's may be less, it's still a higher upfront cost and the avg used BMW owner is going to balk at that price tag.

[Billfitz]

Originally Posted by F32Fleet

Nobody goes through rotors because of corrosion. It just doesn't happen.

+1. It is disconcerting if you leave the car parked outside during a rainstorm and come out the next morning to see the rotors covered in rust. But that rust is only on the surface, and is wiped away by the pads after driving a few hundred feet. The only way you'd get rust serious enough to require replacing the rotors is if you left the car exposed to the elements for a few months without driving it. Even road salt isn't a problem, as it's constantly wiped off the rotors by the pads. Rust only builds up where the pads aren't in contact with the rotors.

In her case she just does not brake them enough.

Not true. The pads are in constant contact with the rotors, but under normal circumstances not with enough pressure to cause excess drag.

[Billfitz]

Originally Posted by Musashi

"Nobody goes through rotors because of corrosion. It just doesn't happen." Where you live, that is correct.

It's also correct where I live, where the winter weather and use of road salt is at least as severe as yours. The last I checked there are no mountains in Ottawa. You're tilting at windmills. You're also arguing with, in my case at least, an experienced mechanic.

[harkes]

Did 7 x 25min at full tilt with one cool down lap in the middle and end on factory rotors with Dixcel Z pads on the front. Car performed like a champ! CCBs are way overkill for anything else than a racing application.

I had a strange problem having to pump the brake pedal, especially after long turns... Pedal went soft at times but no real fade.

(M135i, 430hp, Michelin PS4)

[kern417]

Originally Posted by harkes

Did 7 x 25min at full tilt with one cool down lap in the middle and end on factory rotors with Dixcel Z pads on the front. Car performed like a champ! CCBs are way overkill for anything else than a racing application.

I had a strange problem having to pump the brake pedal, especially after long turns... Pedal went soft at times but no real fade.

(M135i, 430hp, Michelin PS4)

Probably need brake fluid and stainless lines if you don't have them. Once I did pads/lines/fluid I've never had an issue or heard of anyone else having an issue. But OP is hell bent on convincing us that it's just needed for cold weather anyway, since i think we all agree it's overkill for track duty.

[harkes]

Originally Posted by kern417

Probably need brake fluid and stainless lines if you don't have them. Once I did pads/lines/fluid I've never had an issue or heard of anyone else having an issue. But OP is hell bent on convincing us that it's just needed for cold weather anyway, since i think we all agree it's overkill for track duty.

Stoptech brake lines and Motul RBF600...I dont really get it As long as I just pump it sometimes it works great though.

[kern417]

Originally Posted by harkes

Stoptech brake lines and Motul RBF600...I dont really get it As long as I just pump it sometimes it works great though.

Def not ok lol that would freak me out. The only other thing I can think of is air or water in the lines. May need a bleed/flush.

[Musashi]

Originally Posted by harkes

Did 7 x 25min at full tilt with one cool down lap in the middle and end on factory rotors with Dixcel Z pads on the front. Car performed like a champ! CCBs are way overkill for anything else than a racing application.

I had a strange problem having to pump the brake pedal, especially after long turns... Pedal went soft at times but no real fade.

(M135i, 430hp, Michelin PS4)

having driven PCCBs on a 911, Lambo CCBs, steels/CCBs on 3/M3/M4 I will never go back especially if affordable.

[harkes]

I would probably be all over a full set of ceramics if the price came down to....lets say USD4000 including pads and it would be stock fitment. Especially if rotors had a 100.000 miles warranty and pads lasted - lets say half of that.

[Musashi]

if the image does not say it, nothing else is. Stock M Perf are 12000 grams... These are -70% less or 31 lbs less per front set...

[FaRKle!]

So how do you determine EOL? Is it by weight like conventional CCBs?

Do you have rear CCB rotors too?

[Musashi]

Originally Posted by FaRKle!

So how do you determine EOL? Is it by weight like conventional CCBs?

Do you have rear CCB rotors too?

I have an answer- as well as another post below that may irk you- see next entry. EOL is, like with F1 or aviation brakes is thickness, 2mm, but even then they would be safe though less optimal. At some point if we facetime, you will see.

Chopped CCBs indeed vary by weight, and it changes with resin boiling during heat applications; sometimes aggressive cleaners can do it. The 40 yr old chopped tech relies on that shiny mirror like ceramic surface to transfer heat, and that surface remains intact, until such time the internal matrix of the rotor becomes powder, and it crumbles. BMW uses a wear indicator, an exposed matrix that reacts and shows wear. But even then its CCBs are not quite the same as PCCBs, be it also resin and chopped.

In contrast, 3D Continuous needle does not melt inside, and needs some 1800C (mentioned in the articles I sent you) to loose structural integrity. The rotor thus wears its layers but very very very very slowly, much slower than steel. Since rust is never an issue, there never is a post rain, post winter, post car-wash oxidization that further scrapes the surface. Once the pad material is on the 3D CCB, it self reconditions the top surface with each application. Still running the original Brembos in the rear, they are at 23mm (specs are 22.2 - 24 I think). 100,000kms. I also wanted to see the fronts and how they affect the vehicle, and test them thoroughly. The results are so impressive that, next spring when due to replace the rears, I will be ordering a rear, non-drilled set.

[Musashi]

Some recent pics. Terrific in Cold. No dust. No rust. No wear. Pads are nearing a dangerous 0.5mm of wear out of 10mm..

[FaRKle!]

Originally Posted by Musashi

EOL is, like with F1 or aviation brakes is thickness, 2mm, but even then they would be safe though less optimal. At some point if we facetime, you will see.

...

The results are so impressive that, next spring when due to replace the rears, I will be ordering a rear, non-drilled set.

Thanks for the info. Good to know these CCBs don't require any different method from iron rotors to determine EOL.

So where are you ordering the rear set from? Which pad will you use?

Originally Posted by Musashi

I am curious what you, esteemed car enthusiasts, think about this..

If there's demand, why not? Also, high barriers to entry spur innovation around them.


How does the friction coef compare to steel rotors? I know in one of the papers you sent me the CCBs were in the low 0.3x range, but was that due to the CCBs, or was the pad material on the measurement machine? A lot of track pad marketing material claims 0.4-0.6, but like most marketing material, I'm sure there's more to the story and the numbers can't be directly compared without knowing the whole metrology setup.

[Musashi]

Truly extraordinary cold performance. Pre-driving, -17C /1.4F, no squeal no noise. Coefficient of Friction is steady. Modulation and response feel as strong as if driving summertime. Post drive, temperature is 70-90C.