Welcome to Miami: there’s not much braking here

5/3/2022

Braking at Miami International Autodrome and the advantages of Brembo carbon and carbon ceramic materials for road cars

Formula One returns to Florida after a 63 year absence: in 1959, two years before Brembo was established, racing was at Sebring on a track in an old military aerodrome which featured several hairpin bends. This year, racing will take place at the Miami International Autodrome which is located at the Hard Rock Stadium in Miami Gardens.

It is a 5.41 km (3.36 mile) long street circuit with three straight sections and 19 turns but with various differences in height especially between turns 13 and 16. According to Brembo technicians, the Miami International Autodrome falls into the category of circuits with a medium level of difficulty for brakes. On a scale of 1 to 5, it is rated 3 on the difficulty index, the same as the other US track, the Circuit of the Americas.

Brembo carbon doesn't melt at 3,000°C (5,430°F)

Carbon discs were first used in Formula 1 in the 1980s, before spreading to other motorsport competitions. No other element offers the same special combination of light weight, high thermal conductivity and absence of dilation, even at 1,000°C (1,832°F), which is the temperature that the Brembo F1 discs reach.

The density of carbon is 1.7 grams (0.06 oz) per cubic centimeter, compared with 7.8 grams (0.28 oz) for steel and 7.3 grams (0.25 oz) for gray cast iron. Its coefficient of thermal expansion is one-fifteenth of steel and one-eleventh of cast iron. The melting point of carbon is higher than 3,000°C (5,430°F), compared with the 1,200°C (2,190°F) of cast iron and 1,800°C (3,270°F) of steel.

On the road, 3 meters (3.3 yards) make all the difference

Carbon discs aren’t suitable for road use, mainly because the braking system doesn't reach the minimum operating temperatures that this material needs, but also due to high consumption which is not compatible with day-to-day use. Some of their benefits, however, can be found in the carbon-ceramic discs of which Brembo, with Brembo SGL Carbon Ceramic Brakes - a joint venture with SGL Group - is the main worldwide manufacturer.

On average, carbon-ceramic discs allow a saving of 5-6 kg (11-13 lbs) in weight compared to traditional cast iron discs. What's more, their lifespan may even match that of the vehicle they're mounted on. It depends on how it's driven. But, above all, carbon-ceramic guarantees a reduction of about 3 meters (3.3 yards) in the braking distance from 100 km/h to 0 km/h (62 mph - 0 mph) compared with a traditional disc.

Discover all the benefits of carbon-ceramic discs.

Three braking episodes lasting over 115 meters (125.7 yards)

Although there are 19 turns, Formula 1 drivers only have to use the brakes in 4 places at the Miami International Autodrome. It is the lowest value in the championship, lower than the 6 braking episodes at Montreal, Monza and Abu Dhabi. Another record is the 8.3 seconds per lap when the brake system is used, even if it is used for just 7 tenths of a second more in Melbourne.

However, 3 of the 4 braking moments on the Florida track are extremely demanding: in those sections, the drops in speed exceed 200 km/h (124 mph), the braking distance 115 meters (125.7 yards) and the braking time 2.4 seconds. An exception is the braking on turn 4 with very low values for each of these variables including deceleration which is just 2.3G.

Almost 250 km/h (190 mph) less

Of the 4 braking sections at the Miami GP, 3 are classified as very demanding on the brakes and the remaining one is light.

The hardest one on the brake system is turn 17 because the single-seaters come onto it after a 1.3 km (0.8 mile) long straight section. The cars go from 326 km/h (203 mph) to 77 km/h (47.8 mph) in just 2.8 seconds while covering a distance of 131 meters (143.2 yards) whereas the drivers are subjected to 4.6 G of deceleration.

The kingdom of speed

The Hard Rock Stadium has hosted 6 editions of the Super Bowl, with the last one held in 2020: in American football, the quarter backs throw the ball at a top speed of 100 km/h (62 mph). That’s not much compared with the top speed of 160 km/h (99 mph) of the Monster Trucks which raced here from 2002 to 2015. The tennis balls of the Miami Open which has been held here since 2019 go even quicker at over 250 km/h (155.3 mph).