While much of a Formula 1 car is made and designed by each individual F1 team, the brakes are provided by three outside suppliers: Brembo, Messier-Bugatti and Hitco. The brake companies each have strengths and styles of their own. In most cases, the brakes are not mere accessories, nor are they chosen as a result of a commercially driven deal between the brake company and the team. It is generally the drivers who select the brakes they want to use.
And drivers have become pickier about the brakes they choose, in response to the behavior of the series's new racing ,Pirelli tires of 2011.
''With the Pirelli tires the difficulty with braking is in the inside of the corner when the tire is not in the axis of the car,'' said Patrick Dely, a technician from the Messier-Bugatti company, which provides the Carbone Industrie brand brakes to several teams.
''In years past, when there was a competition between Michelin and Bridgestone and the tires were glued to the track, you could have braking energies that were very strong and the driver's sensibility was less important,'' he added. ''Now, you must have a brake that is very efficacious and that the driver can dose, offering a very good sense of feel.''
So far, the Brembo company of Italy is furnishing a brake that works better in this braking in corners. While some teams have longstanding agreements and traditions in using the same provider - as Ferrari does with Brembo - some drivers from teams that have contracts with another provider are requesting the Brembo brakes. At some teams, the two drivers use different brakes.
''Some drivers choose a different kind of pumping on brakes,'' said Vitaly Petrov, a driver at the Lotus Renault team. ''For example, we know that Fernando [Alonso] likes soft brakes, and some drivers like stiff brakes. I prefer to have very stiff brakes because I feel more in control of the locking in the rear and the front. This is why I can't drive with soft brakes, because maybe my left foot is too strong.''
The goal is to cover a lap of the track in as short a time as possible, which means braking as late as possible into corners. Time lost in inefficient braking counts.
The discs and pads in Formula 1 brakes are made of carbon. Formula 1 began using carbon discs in the 1980s, as carbon is lighter and more heat resistant than steel. Formula 1 brakes reach temperatures from 300 to 1,000 degrees Celsius and have to be cooled quickly to maintain their efficiency. A Formula One car can brake from a speed of 300 kilometers, or about 185 miles, per hour to a complete stop in about four seconds.
Like other parts of the Formula 1 car, the brakes are built not for endurance but primarily for speed. In general, the brakes are designed to last a little longer than a single race. Teams use a different set of brakes on the car for the Friday practice sessions, and then add new brakes for Saturday's practice, qualifying and the race the next day.
''There is always a compromise between performance and wear,'' Dely said. ''Some teams will make a choice to have a little less performance but a satisfactory and reassuring life span - because you have to be able to get to the end of the race.''
Carbon brakes are also used on airplanes, and Messier-Bugatti's main business, in fact, is supplying brakes to airplanes. But while a Formula 1 car has a single brake disc per wheel, a Boeing 777 would have about seven such discs per wheel. While the Formula 1 car's brake disc is a maximum of 278 millimeters, or 11 inches, in diameter, with a maximum thickness of 28 millimeters, the airplane disc is usually more than twice that diameter. Unlike on a road car, there is no braking assistance for the driver in a Formula 1 car.
''We press with up to nearly 200 kilos on the brake pedal,'' said Sébastien Buemi, a driver at the Toro Rosso team. ''We do not have assistance like power steering or assisted braking. But this is just as well because it allows us to feel it better. We control the braking much better. When we block the wheels, we are the ones who have to let go of the brake so that it is no longer blocked. A road car does that all by itself.''
''We press really hard at the beginning of a corner,'' he added, ''because when we arrive at 300 k.p.h. it is pretty much impossible to block the wheels because of the inertia, and then we let go of it gently.''
The reaction of the brake to the release of pressure is also different from one brand to another, and that is also a criterion for selection by the drivers. Lewis Hamilton, a driver at McLaren Mercedes, for instance, is very aggressive on releasing the brakes.
''Not all the carbon materials are the same,'' said Andrea Pellegrini, a technician from Brembo. ''There are some materials that do not work as well on the first lap, so it takes more laps to enter the correct range of temperature. Our carbon material is easy to control, to use, so starting from the first braking it is possible to have a good feeling, a good bite, good retardation, and it is one of the things the drivers like the most.''
The brake company technicians work with the drivers not only to learn how the brake system feels in general, but how it feels on specific tracks.
''For example, in Monza or Monte Carlo, it is two different types of circuits,'' Pellegrini said.
''So in Monza you should have a good response when you push on the brake,'' he added. ''In Monte Carlo you should have a good response of the brake but also a good management of the temperature.''
Although the brake companies provide the brakes, the teams are deeply involved in developing the brake cooling systems.
''The biggest change in the brakes over the last five or six years is the cooling and the understanding of how to cool properly with C.F.D.,'' said Sam Michael, the technical director of the Williams team, referring to computational fluid dynamics programs.
''With all the drillings and internal flow paths for the disc and feeds for the caliper and brake pads, we made huge gains,'' he added. ''If you can cool the brakes better internally, if you can run a smaller brake duct scoop - because you don't need as much air because you are more efficient - more air goes to the diffuser and you gain downforce.''
In other words, for aerodynamics reasons engineers want the smallest possible air intake scoops on a car to encourage the least amount of drag that such scoops cause, which slows down the car.
''We are changing little bits and pieces on that all the time,'' Michael said. ''Even though we have had aero upgrades like a front wing or a diffuser, we have changed our brake ducts three times since we launched the car as well. And they will all be little tweaks that improve cooling slightly. And that could be anything from a ducting, a caliper, or a drilling in the disc.''
But listening to the drivers' needs is also the key to gaining lap time, according to Eric Boullier, the director of the Lotus Renault team.
''Either you ease the driver's feeling - which I am in favor of because you can find a couple of tenths - or you impose what you want if you have commercial business behind it,'' he said, referring to team agreements with brake providers.