5 myths to dispel about nascar brakes. Quite unlike Formula 1.

1/22/2018

Race track battles, races with uncertain outcomes right until the last laps, the possibility of success even for teams that invest less money and championship results open until the very last race.

All of this is already reality in the USA thanks to the NASCAR Cup Series - the championship involving about forty drivers battling it out from February to November in the course of 36 races with very heavy cars (around 1,540 kg, double the weight of F1 single-seaters) built by 3 manufacturers (Chevrolet, Ford and Toyota).

For the season that just ended, the winner of the NASCAR Cup Series was Martin Truex Jr. on the Furniture Row Racing team. He used Brembo braking systems throughout the entire season.

The technical regulations keep faith with tradition by envisaging a tubular steel frame with roll-bar, 5.860 cc V8 engines, 4-speed manual transmission, the same fuel and tyres for all cars that are 5.3 metres long by 1.94 metres wide. In terms of appearance, then, they are not all that different from the cars that competed in Nascar event in the 1970s.

Absolutely nothing to do then with Formula 1 cars - and not even the cars competing in the GT championships held in the rest of the world, from DTM to World Endurance (FIA WEC). Yet this does not mean that NASCAR Cup Series cars are old-fashioned because in those areas allowed by regulations, teams carry endless studies and wind tunnel tests. Top speed is utterly essential on the oval tracks.

And the most astonishing thing for those who do not already know the NASCAR Cup Series is the dedication focused on braking systems in terms of construction and usage alike. The 2017 edition of the Nascar Cup Series was won by Martin Truex Jr precisely with Brembo brakes. In the course of 36 races during the season, his Furniture Raw Racing team Toyota used different types of brake discs, calipers and brake pads depending on each race track.

This is why reason we would like to disprove 5 myths about the brakes used in this championship.

1) Brakes are not decisive because races are only run on oval circuits? FALSE

Every year, at least a couple of races are held on road circuits: in 2017 NASCAR Cup Series championship cars competed on the Sonoma Raceway (3.2 km circuit with 10 corners) and at Watkins Glen (5.4 km circuit with 11 corners). Brakes are evidently used on such circuits to reduce speed before taking all corners. On average, brakes are used overall for around twenty to thirty seconds per lap, equivalent to 30 percent of the duration of the race.

2) Brakes are used very little or not at all on oval circuits. FALSE

In medium-long oval circuits, such as Talladega, Daytona and Indianapolis, drivers only use brakes when making pit stops or when yellow flags are waved. The NASCAR Cup Series, however, also involve shorter oval circuits - known as Short Tracks - with laps between 0.8 km and 1.6 km long. In this case, brakes are used to help cars take corners and are used twice per lap over the entire distance of these corners: they are an integral part of the car's setup and are used by drivers to define and hold their preferred trajectories. For example, brakes are used on the Martinsville circuit for approximately 6-7 seconds for each of the two corners. In actual fact, therefore, drivers end up using brakes more than the accelerator.

3) Braking systems are the same for all circuits just like F.1. FALSE

Unlike Formula 1, which uses the same brake caliper model for then entire season, the NASCAR Cup Series involves 3 types of oval circuit and consequently requires the same number of brake calipers because the brakes are used in different ways. Brakes are never used during Super Speedway (4 km oval circuits) events except for pit stops or when yellow flags are waved. Over Intermediate circuits (1.6 to 4 km oval tracks), brakes are used to a very limited extent while Short Track events mean that the braking system remains in operation for the entire corner. As a result, smaller calipers are used for Super Speedway events, while Short Track requires larger ones and Intermediate circuits medium-sized calipers. Moreover, the dimensions of the discs used in Formula 1 are the same for the entire season and only the ventilation holes vary, for NASCAR events the diameter and thickness of the front discs also change depending on the type of circuit.

4) Braking systems are identical for all drivers. FALSE

In order to keep caliper and disc temperatures under control, every team requires different types of ventilation in relation to the aerodynamic needs of each individual vehicle.

To meet these needs, Brembo researches specific solutions for disc ventilation channels. Moreover, since the same team may even have drivers with different braking styles (some drivers adopt a single-seater style, with initially intense and then decreasing braking and those who prefer the opposite approach), two team-mates may use different friction materials and different discs.

5) Braking systems are very heavy compared to those used in F1, Dtm and GT championships. FALSE

One would imagine that having to brake cars weighing more that one and a half tonnes would require imposing braking systems. Yet the Brembo 6-piston front enbloc caliper for Short Track cars weighs only 2.8 kg and the front 4-piston caliper for the Super Speedway weighs no more than 2.3 kg. The cast-iron discs obviously weigh more than the carbon discs used in Formula 1: for NASCAR, a 328 mm diameter by 42 mm thick disc for Short Tracks events weighs in at 10.5 kg while a super light disc having a diameter of 328 mm by 28 mm thick for Super Speedway weighs 4.9 kg.