Audi to Offer High-Performance Ceramic Brakes on A8 W12

Ceramic Discs to Last Up to 300,000 KM

While airbags, safety cells and stability control systems are hailed as the latest and greatest features designed to protect the lives of occupants of cars, the latest revolution comes in the form of brakes. Developed on race tracks in competition, as well as in safety labs, we have come to associate ceramic brakes with pedigree sports brands, such as Ferrari and Porsche. Offered on vehicles such as the F430, Enzo, Carrera GT and 911 Carrera S, this kind of technology is limited to the utmost high-performance driving machines and is out of the reach of the general public. That is, until recently, as Audi has announced that it will be offering ceramic brakes on its flagship vehicles, the A8 W12 and long-wheelbase A8L W12.

So, what exactly is a ceramic brake? The difference is not in the caliper, but rather, in the disc itself. Normal discs are made of steel, which is a formidable material for the job. With ceramic brakes, the material of choice is silicon carbide, an abrasion-resistant crystalline compound thats similar to diamond in structure. Embedded into the disc are fibers of carbon, which help the silicon carbide absorb and cope with the immense stresses that a brake disc would normally endure. Because of the material used in the composition of the discs, the brakes also have a uniform coefficient of friction, which provides consistent pedal feel and braking distances, regardless of weather or temperature.

The advantages that ceramic brakes have over conventional ones are astonishing from a performance perspective. They are even more evident under high-stress situations, where heavy and constant braking is required, such as during racing. If youve ever seen racing cars in action, sometimes you may catch a glimpse of a red-hot rotor, glowing from behind the wheel. From a performance standpoint, ceramic brakes are able to function perfectly, even under ultra-high heat. They can not only withstand heat better, but dissipate it faster, helping to eliminate brake fade. But the A8, even in W12 guise, is nowhere near any of the aforementioned cars in terms of performance, so the question remains - why offer them?

Their size alone also dictates that A8s equipped with carbon ceramic discs must wear heavier 19-inch alloy wheels. The weight saved will make an immense difference in the way that the car drives and performs; lighter discs mean less unsprung weight (weight not supported by the cars suspension), which in turn means a better ride, and sharper cornering. Ceramic brakes also produce less dust than conventional steel discs, meaning that those sparkly 19-inch alloy wheels will stay cleaner, longer.

The use of ceramic brakes also offers other advantages to the A8. For one, because of the abrasion-resistant nature of the carbon ceramic disc, they are far more durable than regular steel discs. Audi claims that the discs on the A8 will last up to 300,000 km (186,000 miles), approximately four times the life expectancy of a conventional steel disc, and a distance thats well beyond what most people will rack up over a cars lifetime. Also, it is worth noting that the sound frequency emitted during braking by carbon ceramic brakes is inaudible to the human ear, and therefore, the brakes themselves are quieter.

But theres a reason why ceramic brakes are offered only on A8 W12 models - their cost. New technology isnt cheap, particularly a technology that dramatically improves every area of the brake. While Audi hasnt released pricing for the brakes, looking at the marketplace should give an idea. Currently, Porsche offers its high-performance 911 Carrera S with the option of ceramic brakes (PCCB) at a premium of $8,150, making it the most expensive option on a list that includes electrically adjustable racing seats and European delivery! While its true that the PCCB system is geared towards high- performance use, whereas the A8 is for daily use, the price should not differ significantly. The ceramic brake option will be added to the A8 W12s lengthy option list as of this July.