I will tell you how Brembo has revolutionized brakes for the Le Mans 24 hours

6/7/2019

Carbon,aluminum/lithium clamps,spline fittings and miniaturizations: brakes help you to go faster too.

In addition to forty years of experience in Formula 1, Brembo has also a long history in Endurance races, in all Le Mans 24 hour races: an experience full of success as the 28 outright victories prove, all achieved by vehicles equipped with Brembo brakes in the last 31 years.

In recent years not only have vehicles evolved incredibly (just think of engines changing from petrol, to diesel, to hybrid) but braking systems too have continuously evolved.
Originally the best braking system was the one which was the most effective in slowing the vehicle down.

Recently, though, brakes have also had a significant effect on acceleration and speed on bends, thanks to reductions in size and weight of the non-suspended elements, without compromising reliability and durability.

Increased durability of the discs

The innovations introduced by Brembo, which have completely changed the profile of braking systems used by LMP1 in recent years have involved all the various components of the braking structure. The main innovation concerning carbon disks for endurance competitions in recent years has been the reduction of wear and consequently longer durability. In a 24 hour race, avoiding the need to replace worn-out disks can be crucial, saving precious time.

Thanks to the introduction of a new friction material, reducing wear considerably and guaranteeing a more efficient thermal conductivity, as early as 2001 Brembo enabled the R8 Audi of the Joest Team driven by Frank Biela, Emanuele Pirro and Tom Kristensen to win the race without replacing disks and brake pads even once.

The incredibly low wear has helped to maintain consistent and repeatable performance from start to finish of the race, a crucial aspect in a race where track grip conditions constantly change.

Caliper weight reduction

As for the brake calipers, Brembo's most important innovation concerns the maximization of the weight/stiffness correlation, in order to ensure maximum stiffness with the least caliper body weight without jeopardizing its reliability.

After a careful study, monobloc calipers have been introduced in 2006 in aluminum/lithium, a significant development in terms of weight and stiffness compared to the aluminum calipers used up until then.

Made from a solid block, they are the perfect solution for single-seater cars used in endurance races.

How to take on 24 hours of braking at Le Mans

Just a bit lower performance, but by no means slow, are the Grand Touring Endurance (GTE) cars, sport replicas of the fastest street supercars in the world. They, in turn, are divided into GTE-Pro and GTE-Am. These are very different cars from one another and they also differ in the Brembo braking systems used. Let's take a close-up look at the main differences...

Optimised fasteners between the cup and the braking surface

Brembo has also introduced an innovation in the fixing between the brake bell and the braking surface. The abrasive material with metal bushes, used up to some ten years ago by LMP1 (and widely used until 2016 among LMP2 for reasons of cost) has been replaced since 2008 by a material with splines.

This is a solution adapted from Formula 1 which involves a direct dragging /braking on the disk by the bell-shaped part which is made of titanium, without the interposition of joining elements (the metal bushes) between the two.

The advantages of this solution are considerable, both in terms of weight and improved application of the braking force. Moreover, in previous years ventilation was severely limited because the fixings of the brake housing caused obstruction to the air intake.
Now, with the introduction of the spline, a kind of tooth-wheeled gearing, the inside part of the disk is open to the flow of air.

Reduction in disc and pad thickness

Recently Brembo's attention has been focused on the size optimization of disks and brake pads, to reduce the non-suspended masses to the minimum: the prototype disks that only 10 years ago were 35mm thick now measure 30-32mm.

Similarly, the thickness of the carbon of the brake pads has decreased from 31,5 mm to a maximum of 26 mm. This may not seem much but on LMP1 prototypes each weight reduction, of as little as 1 kilogram, will save some tenths of a second per lap. For the GT (GTE and GTE-pro) vehicles, instead, the regulations expressly forbid the use of brake pads in carbon.

This is why – for these vehicles – Brembo supplies disks with cast iron braking surface and aluminum bell, which are more similar to the ones used on everyday vehicles, at least in the materials used.
Teams can then choose from the different types of Brembo braking surfaces to find the best compromise between the bite of the brakes and the durability of disks and brake pads.

Formula 1 vs Le Mans: a comparison of Brembo braking systems

There is a great difference between the front and back brake disk diameter, depending on both the individual team choices and on the vehicle balance. Brembo also supplies many GT teams with monobloc calipers, made from a solid piece of material or cast, but designed specifically for endurance races.

We take particular care of GT category vehicles, super cars such as Porsche, Ferrari, Aston Martin, Corvette or Dodge which in the majority of cases are equipped with Brembo braking systems even in their road version. In this case our effort two-fold: firstly we want to further improve the standard Brembo braking system, and secondly these vehicles derive from the standard version. Research on the track can have a knock-off effect for the production of standard braking systems.