When pondering over improving or modifying your car for the first time, you have plenty of options. From tuning up the engine, adding a cold air intake system, cutting the exhaust in half, or adding a set of enhanced shock absorbers. But if you ask me, the most important upgrade you should tend to are the brakes. We then ask ourselves… Carbon ceramic brake pads, are they worth the price?
It’s good to shop around, of course. Good brakes are second to none. Your car might be quicker in a straight line and could take on corners like a fly. But if you can’t stop your car in time, performance gains and enhancements thereafter are practically worthless. Hence, why quite a few racing drivers (if you too want to learn how to become a race car driver) and tuners have always recommended upping your car’s braking power as the first big upgrade.
Carbon ceramic brake pads have reigned supreme on race tracks for decades. From Formula 1 (speaking of, do check out our write-up on Indy Car vs Formula 1) to GT racers and Le Mans-winning champions, carbon brakes have proved their mettle. Nowadays, many performance cars offer carbon ceramics as optional extras. Sometimes, they throw them in for free. But if you’re looking to make that big leap forward, are carbon ceramic brake pads worth it?
What’s The Deal With Carbon Ceramic Brake Pads, Anyway?
Interestingly, carbon ceramic brake pads didn’t start life in automotive applications. Instead, it was first implemented in the 1970s within trains. More specifically, high-speed rail required optimal braking power and could stop those train cars reliably. Trains needed brakes that won’t wear out or fade all too quickly. The aerospace industry had a similar requirement for carbonized brakes, too.
The famed Concorde supersonic jet was a good example. For a plane that could fly at up to twice the speed of sound, it needed meaty brakes to stop it once it got to the runway. In 1976, Concorde used a carbon-carbon braking system on their planes. To be precise, they are graphite-reinforced carbon fiber brakes. Unlike regular brakes, these don’t burn out when you stop too quickly.
From then on, carbon brakes became smaller and eventually made it to race cars. Early F1 cars by the end of the 70s had carbon braking systems. At the time, a set of carbon brake pads and rotors were ludicrously expensive. Moreover, they required frequent upkeep such as a replacement every 1,000 kilometers – or 621 miles – and didn’t really work all that well in wet or cold climates.
How Has Carbon Ceramic Brake Pads Evolved Over The Years?
The older carbonized braking systems have evolved significantly into the carbon ceramics brakes that we’re well acquainted with nowadays. Thanks to the addition of ceramic material into the carbon, the combined carbon ceramic brake pads are far more durable. They can last for thousands of miles just like regular iron or steel brakes, and maintain their performance throughout with minimal wear.
Additionally, silica carbide was added into the mix along with carbon and ceramics. In doing so, a typical carbon ceramic brake now has improved resistance against shock, excess thermal exposure, as well as oxidation. Thus, they can work for longer, and provide just as much stopping force at a wide range of temperatures and conditions. You don’t have to worry about chilly weather.
Over time, what was once the same coating used on space shuttles to battle heat and friction, most can option a set of carbon ceramic brake – assuming you can afford one – on your car. Besides lower costs as it trickled down, carbon ceramic brake pads are dependable, reliable, and more functional for daily use. Plus, they’re easier than ever to modulate and control, without being too grabby.
What Goes Into Making Carbon Ceramic Brake Pads?
Some of the most iconic supercars ever made have carbon ceramic brake pads. Think of the Bugatti Veyron, McLaren F1, Ferrari Enzo, Porsche Carrera GT, and more. There’s a good reason why only the top dogs get CCB – or carbon ceramic brakes. Simply put, they’re expensive. An entire set of CCB can cost a mere mortal between $3,000 to $15,000 on average. But more on that later.
There are merits behind why carbon ceramic brake pads are so expensive, however. Namely, they’re difficult to manufacture. Its production process is meticulous, with some of the better brakes taking nearly a month or more to build. That’s just one disc, mind you. Now, multiply that by four, and you start to get an idea as to why it’s common to shell out five digits for some new brakes.
First off, the mixture of carbon fiber and silicone resin is poured into molds. Once poured in, they’ll be placed under 20,000kg – or a whopping 44,000lbs – of pressure. At the same time, the mix will be baked at 200°C – or 392°F – before rapidly being cooled. This creates the core structure of the carbon ceramic brakes. To solidify it, the mold is once again heated to 1,000°C – or 1,832°F – for two days.
After it’s been baking for two whole days or more, sprinkles of silicon power are added to the mold to finish it off. Finally, it’s brought back to be heated up to 1,700°C – or 3,092°F – in a vacuum for at least 24 hours. This is a generalized step-by-step process that will gradually harden the carbon fiber and silica carbide compound together. Last but not least, a spray of anti-oxidation coating will top it all off.
What Are The Different Type Of Carbon Ceramic Brake Pads And Discs?
Out of the other end of that lengthy and intricate manufacturing process, you end up with not one, but two contrasting versions of carbonized brakes. It’s crucial to understand them, as we’re looking at the small nuances in the material used for the overall construction and finish of the brakes. Why is it so important? Well, remember that brake discs – or rotors – need to absorb and dissipate heat.
A lot of heat, in fact, to best emit friction that’ll slow down your car. Moreover, the type of carbon material used will need to withstand the high clamping pressures of your brake calipers, as well as your car’s brake torque. In other words, the power of the braking system. Hence, why we get several types of brake discs, as each one is best suited for differing applications and scenarios.
Primarily, we can split them into three (one of which isn’t technically carbon, but it makes for a good comparison)…
1. Grey Iron Brakes
These aren’t carbon, but it’s neat to see how we’ve moved on from iron to carbon. The term “grey” there is used to denote the use of graphite in the braking material and construction. In the 1960s, carmakers began a marked transition from drum-style brakes to modernized brake discs. Iron – and later, steel – discs saw widespread adoption till today, where most cars are fitted with them.
A lot of people do like to use the nickname “steel” or “steelies” to describe grey iron disc brakes, but that’s not entirely true. They’re quite distinct from typical steel brakes and are far more popular by comparison. To simplify, grey iron brakes offer the best-of-both-worlds as far as brake performance is concerned. They stop decently well and are reliable enough that you can afford to use them.
These iron brakes have great thermal conductivity, tensile and mechanical strength, as well as good resistance against wear. Alternatively, they’re malleable, so carmakers could modify their internal structure ever so slightly to fit different needs. Should that not be enough, it’s common to find grey iron brakes be combined with a diverse array of elements to tweak their characteristics.
Carbon, molybdenum, and silicon are the most usual additions to iron brake compounds. This makes iron discs incredibly versatile, whether you need ultra-durable brakes or one that could halt your car in a pinch. The processes for casting and machining them are notably simpler. As a result, you don’t have to spend a fortune to get a pair, and it could be adopted for a broad series of uses.
2. Carbon-Carbon (CC) Brakes
Although we mostly see carbon ceramic brake pads these days, carbon-carbon is still widely used in certain industries. Regular passenger vehicles, not so much. But aircraft brakes are predominantly carbon-carbon. Another place where you’d see carbon-carbon is in the top leagues of motorsport, like Formula 1 and IndyCar. But why are carbon-carbon brakes still being used while CCB is around?
There are a few serious rationales for this. For starters, CC brakes are outstandingly lightweight, and they carry many thermal benefits. They’re highly resistant to thermal shock (i.e. rapid heating and cooling), have a minimal thermal expansion, and can withstand supremely high temperatures. At those blazing hot temperatures, carbon-carbon actually provides even greater friction.
Unlike other types of brakes, the pads on CC braking systems are identical in material with the discs that they’ll be rubbing against. This is one of the many factors that lead to CC only having been fitted to certain applications. The manufacturing of carbon-carbon brakes is time-consuming, complex, energy-intensive, and necessitates using specialized equipment following weeks of production.
Suffice it to say, but they’re endlessly expensive and are unobtanium for regular folks. If that’s not bad enough, carbon-carbon brakes – as we’ve touched upon earlier – wear at an accelerated pace, and generate a preposterous volume of dust. Worse of all, they can’t generate sufficient friction at lower temperatures. Hence, why you won’t see regular cars on the road with CC brakes.
3. Carbon Ceramic Matrix (CCM), Ceramic Matrix Composite (CMC), Porsche’s Carbon Ceramic Brakes (PCCB), Etc.
A step down from the hardcore carbon-carbon brakes, we have carbon ceramic brake pads, which are rapidly gaining in popularity. There are numerous derivatives and formulations that have been molded in recent years. For instance, take Porsche’s unique take and design of carbon ceramics, or better known as PCCB. Either way, they work the same way, with varied braking performance.
Some are more fine-tuned for stopping power, while others are made to last longer than others. The defining aspect that makes it superior to CC brakes is that ceramic matrix layers – as well as silica carbide – mixed into the carbon. Consequently, ceramic makes then add a layer of longevity, and it can work far better with road cars as it doesn’t need to heat up too much to start biting hard.
Nonetheless, we do have to clear up the misconception that carbon-carbon and carbon ceramics are one and the same. On the contrary, they’re both very distinct from one another, especially when it comes down to braking performance. Carbon-carbon brakes are the pinnacle of stopping power as we’ve seen it in the extreme ends of motorsport such as F1, where speeds regularly exceed 200++mph.
Carbon ceramic brakes, on the other hand, are inherently road-going brakes. They’re not designed to handle the same amount of abuse as track-honed CC brakes. Nor could they stop you as quickly and forcefully as it may with carbon-carbon brakes. Folks get this misconstrued frequently, so let’s be clear… The CCM brakes on a Ferrari road car aren’t the same as the CC brakes on a Ferrari F1 car.
What Are The Benefits Of Carbon Ceramic Brake Pads And Discs?
Since we’ve cleared that up, do carbon ceramic brake pads offer any noticeable advantage over the stock iron (or perhaps, steel) brakes on your car? Seeing the gargantuan expense, how do you know that you’re getting your money’s worth? To help you out, here are some of the many upsides to cars kitted out with full carbon ceramics on them…
1. Reduction In Overall Weight And Unsprung Mass
In the geekier ends of automotive engineering, the term “unsprung mass” gets thrown in every now and then. Unsprung mass refers to the amount of weight that your car carries which isn’t supported by the suspension. In other words, parts like your tires, wheels, as well as brakes count as unsprung mass, as they aren’t bouncing around with your shocks and struts. Calibrating this is crucial.
Reducing weight on your car entails improved performance and dynamics. Though, if you focus that dieting with unsprung mass, the benefits are twofold. With less unsprung mass, you’ll notice better acceleration, cornering, braking, and agility. Additionally, reduced mass below the suspension may bring you improved fuel economy and comfort, as the car’s ride becomes more poised.
CCM does play a fairly substantial role in weight reduction, mind. On average, carbon ceramic brake pads weigh around 60% less than a typical cast (grey) iron brake. Pair that with lighter calipers and pads, and the entire braking system could take huge chunks out of your car’s heft. This is one great way to further optimize your vehicle’s performance, especially in regards to handling.
2. High Resistance Against Abrasion And Wear
The layers of ceramic matrix sewn and embedded into carbon ceramic brakes make it exceptionally durable. It’s not just rock hard, but also has low porosity. Plus, it’s resistant against the brake pads continuously rubbing against it, and could happily sustain higher temperatures better than grey iron brakes. Albeit, extremely high temperatures can still wear off the outer coating of carbon ceramics.
Otherwise, the advantages are bountiful. Relatively heavy use, such as braking hard on a track, isn’t going to wear out CCM brakes to fade after just a few laps. Once you leave the track and out into an open road, CCM remains unfazed to regular driving, as well. With more moderate usage, it’s possible for CCM brake discs to last up to 200,000 miles, or sometimes the entire lifetime of the car.
3. Minimal Release Of Brake Dust
One of the worst aspects of car maintenance is having to wash off the thick layers of brake dust left behind on your wheels and tires. On most cars, that dusty residue is iron compound scrubbed and ground off the surface of regular cast-iron brake discs. Because CCM is resistant to abrasion and is quite hard, you won’t find nearly as much dust being sanded out of carbon ceramic brakes.
4. Doesn’t Make As Much NVH
That’s Noise, Vibration, and Harshness, to you and me. It’s to gauge just how loud, shaky, or harsh a car is to drive. Carbon ceramics are generally quieter and smoother to operate compared to an old-school iron disc brake. There are exceptions, however. Some CCM brakes can emit a sharp squealing sound when they’re cold or if you’re braking at lower speeds. But they are steadily improving.
5. Unaffected By Warping Or Deformation
Lower upkeep is a given with CCM, typically. For starters, they don’t corrode as iron brakes do once exposed to road salt or moisture. Neither carbon nor ceramic rusts. Besides that, CCM brakes can be impervious to warping and deformation over time. This can happen regularly with iron brake discs, thanks to the high heat and thermal shock (rapid cooling and heating) that it undergoes.
Carbon ceramic, on the other hand, is more than fine at higher temperatures, such as when you’re going hard on a track. As hot as it might get, CCM brakes won’t deform and warp. With brake discs that remain as smooth as ever, the rest of your brakes won’t wear as quickly, either. This means you get even pad wear and can prevent damage to the calipers or brake pads.
What Are The Downsides To Carbon Ceramic Brake Pads And Discs?
Funnily enough, carbon ceramic brakes may not even be as good for intense track driving as they might seem. Not my words, mind you, but that of Porsche’s own engineers. They claim that PCCB may not be the best choice if you’re keen to track your car frequently. Many have also documented their first-hand experiences, with issues of the brakes burning up, or about its difficulty to find suitable pads…
1. Potential For Oxidation At Higher Temperatures
One of the last stations during manufacturing before a set of carbon ceramics is boxed up and sold is the application of a coating around the exterior. This coating is meant to protect the carbon fiber layers from burning up too much and turning into carbon dioxide. For the most part, this coating is adequate to protect most CCM brakes at higher temperatures. But it’s not perfect as of yet.
Under severe conditions, let’s say, doing repeated track days for hours at a time, it can still oxidize if given the chance. This is especially true nowadays, as cars continually tack on more horsepower and inertia for the brakes to grind to a halt. There are times where an almost-new set of carbon ceramic brakes could burn up and wear due to excessive oxidation within just a day of circuit driving.
When you eventually overcome that exterior coating, you’ll see deep grooves and rash-like spots on the disc face. This is your sign that the carbon ceramic compound is heating up into a gas – carbon dioxide. You could fix this by resurfacing the brake discs’ top surface. But as expensive as this is, it can only be done a few times. After that, you’ll have to scrap the brakes entirely.
2. High Concentration Of Temperature Causes Added Wear
Yes, carbon ceramic brake pads can work just as well at higher temperatures. It doesn’t work both ways for the rest of the braking system, though. When you’re leaning in on the brakes on the track, CCM brakes could heat up to over 1,800°F. In contrast, iron brake discs don’t usually go higher than 1,000°F. All this heat will flow and affect the rest of your brakes… Pads, calipers, pistons, seals.
The brake fluid might even start boiling at this point. Furthermore, you’ll be called on to replace the brake pads and calipers more frequently than you should. One other double-edged sword is carbon ceramic brakes’ low thermal conductivity. Since heat doesn’t flow as much through carbon as it does with iron, this means most of the heat will be concentrated on certain parts of your CCM brakes.
As a result, carbon ceramics may be harder to cool down than iron discs. Instead of just channeling cold air for iron brakes, carbon ceramics dissipate heat through radiation. Thus, it can’t leverage the cooling abilities of most standard non-ceramic-fit cars, like brake ducts. Instead, carbon ceramics require a large surface area to readily radiate their heat as much as is necessary.
3. Expensive Pads And Fitment Required
Here’s something to consider if you’re upgrading to CCMs, the expense won’t just be limited to the brake discs alone. You’ll need specialty pads that work exclusively with carbon ceramics. Tying into what we said earlier about thermal conductivity, CCM-first brake pads are usually much larger and pricier. Otherwise, choosing incompatible pads could possibly eat through your carbon ceramics.
Unfortunately, only a limited selection of pads are available on the market right now that could be readily paired with CCMs. Speaking of expense, we’ve mentioned already just how expensive a new replacement carbon ceramic set is. On average, you’re looking at around $8,000 for all four corners. As we’ve learned so far, they might not last as long if you’re routinely tracking your car.
In addition, your current wheel (size) may or may not be big enough to accommodate CCM brakes. Going back to how carbon ceramic brake pads cool, they need large diameter wheels to sufficiently vent. If not, brake cooling and performance will suffer. Adding larger wheels and tires may negate what unsprung mass you’ve lost, though. Usually, you’ll need 19-inch wheels or larger ones.
4. Sensitive And Hard To Get Used To
An important ritual to complete after getting new brakes is called “bedding in”. This is where you’ll be asked to rapidly heat up and cool down the brakes while driving. In short, it’s a way of breaking into your brakes to get them going. While the bedding-in process is quite simple to complete with iron brakes, CCMs are more sensitive. You’ll have to jump through more hoops to get it done.
“Sensitive” is going to be mentioned a lot when caring for carbon ceramics, as they’re prone to get damaged. On the track, for instance, can lead to numerous encounters with debris that’ll impact your brakes at speed. This won’t deter iron brakes. With CCMs, on the other hand, stone chips or loose rocks hitting them could severely chip and ruin your expensive carbon ceramic brake pads.
Brake Pads Facts: What You Need to Know
- Brake systems convert kinetic energy into thermal energy through friction from brake pads.
- Bertha Benz is credited with creating the first brake pads out of leather for an early patent of their automobile in 1888.
- Brake pads were initially made from asbestos, but were later replaced by organic brake pads after the discovery that asbestos was a highly-potent carcinogen.
- Organic brake pads generate moderate friction, are quieter, and don’t put much stress on brake rotors.
- Ceramic brake pads are very durable, produce less dust and noise, and can perform in a broader range of temperatures and driving conditions.
- Semi-metallic brake pads use fillers to create the pad compound and offer improved braking performance in a comprehensive range of temperatures and conditions.
- Metallic brake pads tend to be noisier, put more stress on the brake system, and produce more brake dust than ceramic and organic pads.
- The choice between ceramic, semi-metallic, and organic brake pads depends on the vehicle manufacturer’s recommendations, ride expectation, and driving style.
- Brake pads need to be inspected and replaced regularly, and the choice between brake pad types is up to the driver.
- The comparative differences between organic, ceramic, and metallic brake pads include price, performance, noise, and wear and tear on the brake system.
Final Thoughts On Carbon Ceramic Brake Pads
The question you might ask at the end of reading this would probably be, “Do I need carbon ceramic brakes on my car?” Let’s assume you have pockets deep enough that you could feasibly cash out up to $15,000 for a set of CCM brakes. And… Just to make things easier, let’s say you have wheels big enough to fit them, with sufficient room all-around to keep them cool. Well…
IF you’re an enthusiastic track day goer and want maximal performance to break the lap record at your local circuit, then sure. Carbon ceramics offer the best stopping power out of any current brake design and could take on the extra heat. But do bear in mind that continuous heavy use of the CCM brakes, like going 100 laps at a time, could burn and wear them out fairly quickly.
IF you’re keen to upgrade the brakes on your daily driver, then it makes the most sense here. While you’re not likely to extract its performance capabilities, your stopping distance is shortened. Plus, it lasts for a long time – under moderate braking – and doesn’t release plumes of brake dust. Servicing aside, you can also enjoy greater comfort, with fewer unwanted noises and vibrations.