MEDIA INFORMATION Le Castellet, March 27-28, 2015
MICHELIN’s latest endurance racing tyres take to the track at the 2015 FIA World Endurance Championship pre-season Prologue
The FIA World Endurance Championship’s Prologue test at Le Castellet, France, on March 27-28, will mark the first public appearance of Michelin’s 2015 endurance racing tyres. Michelin Motorsport’s technical staff will use the two days to perform a detailed analyse of the new tyres’ performance, and the range provided this season by the French company to its partners features some notable evolutions. The ferocity of the competition seen in the discipline has led all the players to push out the envelope in their respective fields, notably in the LM P1 and LM P2 prototype classes.
New cars have emerged from the winter break, while quality teams have joined the FIA WEC’s ranks, not to mention the incorporation of a new race at Germany’s Nürburgring as replacement for the Brazilian round at Interlagos which is currently undergoing transformation work. Together, these changes have had a significant impact and played a key part in the development of Michelin’s endurance racing tyres for 2015.
At Le Castellet, Michelin will be able to count on the attendance of 19 of the 28 registered cars, although it will only be represented in the LM P2 class by Strakka Racing at the Prologue.
New tyres for Michelin’s LM P1 partners
The LM P1 teams were particularly active over the winter break and will be putting numerous new developments through their paces at Le Castellet. Audi Sport has made extensive modifications to the R18 e-tron quattro and has even switched from the 2MJ to the 4MJ ERS category. Porsche’s programme focused essentially on the 919 Hybrid’s aerodynamics and front suspension, while Toyota conducted an overall optimisation reappraisal of the TS040 Hybrid. Meanwhile, Michelin worked on its 2015-generation solutions for its LM P1 partners. For the 2015 FIA WEC, the French firm's engineers have designed new tyres that cover more specific temperature windows. Each one is consequently more competitive in its particular temperature range which means the LM P1 teams will be able to adapt their tyre strategies to different scenarios.
Audi Sport is one of the teams that have introduced the most far-reaching changes to its car in the form of new solutions for its aero package and a review of its hybrid powertrain. The Audi R18 e-tron quattro keeps the same name but has made progress in an area that is capital in endurance racing: energy efficiency. The prototype has switched from the 2MJ to the 4MJ ERS category and its electric motor now delivers 200kW (272hp), while its four-litre V6 turbo-diesel engine boats a power output of 558 horsepower. The flywheel-based energy storage system, which is located next to the driver inside the cockpit, can stock up to 700 kilojoules, an increase of 17 percent over last season.
Despite these changes, the weight of the Audi R18 e-tron quattro hasn’t budged and remains at 870kg. At the same time, by opting for the next ERS bracket up, the team’s engineers have calculated they will achieve a fuel saving of 2.5 percent per lap. During this time, Michelin worked closely with its German partner to adapt its tyres to the car’s new performance characteristics.
[email protected] MEDIA INFORMATION Le Castellet, March 27-28, 2015 While Audi Sport worked through its programme, its two chief rivals were equally busy, since the Toyota TS040 Hybrid and the Porsche 919 Hybrid also feature significant new developments.
Although its exterior appearance is essentially identical that of 2014, the Toyota TS040 Hybrid has evolved in nearly every domain. Last year’s world championship-winning team is targeting further title honours this season, along with victory at the prestigious Le Mans 24 Hours which the Japanese carmaker has yet to win.
To give it the very best chances of achieving these objectives, the aerodynamics and powertrain of the Toyota TS040 Hybrid have both been optimised with the introduction of new solutions engineered to enhance the car’s performance and reliability.
Porsche’s efforts focused on the aerodynamics and front suspension of the 919 Hybrid and the resulting new aero package will be used for the 2015 WEC’s first two six-hour races at Silverstone, England, and Spa, Belgium, on April 12 and May 2 respectively.
At the same time, the Stuttgart-based make has revised the car’s front suspension, a job which entailed collaborating closely with Michelin on performance optimisation. The chief aim of this joint work was to improve tyre consistency and longevity.
As far as the privateer teams are concerned, Rebellion Racing has been working hard on the development of the 2015 version of the R-One and the driver line-ups of the two cars that will make their debut at Le Mans on June 13-14 have been revealed. Unlike Rebellion Racing, newcomer Team byKolles is attending the FIA WEC Prologue with its new CLM P1/01-AER. Both these teams will race on Michelin LM P1 tyres.
Importantly, the Michelin tyres designed for the LM P1 prototypes in 2015 are five to six centimetres narrower and around two kilograms lighter each, with no detriment to either their performance or longevity.
Michelin’s LM P1 tyre range: slicks, ‘Hybrids’ and rain tyres.
Michelin’s LMP1 slicks are available in a choice of two compounds (SOFT and MEDIUM) and two temperature windows (HIGH and LOW):
- SOFT ‘LOW TEMPERATURES’, - SOFT ‘HIGH TEMPERATURES’, - MEDIUM ‘HIGH TEMPERATURES’.
Audi Sport, Porsche Motorsport and Toyota Racing benefit from bespoke tyres tailored to the specific characteristics of their respective cars.
The Michelin Hybrid tyre appeared for the first time as a replacement solution for intermediate tyres in 2012. Its revolutionary compound enables it to race in wet conditions, despite its ‘slick’, pattern-less tread.
There are two types of wet weather tyre: WET and FULL WET.
The size of MICHELIN’s front and rear LM P1 endurance tyres is 31/71-18.
[email protected] MEDIA INFORMATION Le Castellet, March 27-28, 2015 New LM P2 partners for Michelin and new LM P2 tyres
After claiming the 2014 FIA WEC Teams’ title with its partner SMP Racing, Michelin is keen to continue competing head-to-head with rival brands. The arrival of new teams and, above all, new cars in the LM P2 class will certainly shake up the smaller prototype class.
Michelin Motorsport has effectively developed a new range of tyres for the 2015 FIA WEC and European Le Mans Series. These tyres, which are the fruit of a test programme that took in a broad variety of circuits and temperature conditions, are available for the first time at the FIA WEC Prologue and will subsequently appear at April’s 6 Hours of Silverstone.
They are adapted to the different cars run by Michelin’s partner teams. The latters’ ranks notably include Strakka Racing, its only LM P2 partner at world championship level with the new Strakka-Dome S103-Nissan, the result of an Anglo-Japanese partnership between Strakka and Dome Racing.
In the 2015 ELMS, Michelin is working with SMP Racing and its new BR Engineering- developed BR01-Zytek, as well as with KROHN Racing (Ligier JS P2-Nissan).
As was the case last season, the sizes of the LM P2 prototype tyres are 30/65-18 (front) and 31/71-18 (rear). The range features three types of slick (MEDIUM LOW TEMPERATURES, MEDIUM and MEDIUM Plus) and two wet weather tyres (WET and FULL WET).
New LM GTE Michelin tyres
Michelin has also introduced new tyres for its partners in the LM GTE Pro and AM classes. Engineers from Michelin Motorsport worked over the winter break to increase the efficiency of the French company’s constructions and compounds, as well as the pattern of its rain tyres.
As is the case in the other classes, the cars fielded by Aston Martin Racing, Ferrari AF Corse and Porsche Team Manthey have evolved since last season and Michelin wanted to match these changes with new tyres (front: 30/68-18 / rear: 31/71-18).
Michelin’s partners will be able to choose from three types of slick (different compounds and temperature windows), as well as from two new rain tyres which have just completed their fine-tuning phase.
In line with the spirit of the championship, the LM GTE AM cars will use the Michelin tyres that were available for their ‘Pro’ counterparts in 2014.
Focus: the development of MICHELIN’s endurance racing tyres by Nicolas Goubert (Technical Director, Michelin Motorsport)
“The design of a new tyre begins on a digital simulator using data provided by our partners covering the constraints to which the tyres were subjected during development testing at different circuits.
[email protected] MEDIA INFORMATION Le Castellet, March 27-28, 2015 Thanks to this information, we do not require details of the car’s characteristics, such as its powertrain, for example, or its power output, weight distribution or aerodynamic downforce.
This means the technical specification can remain confidential while tyre development gets underway.
Endurance racing tyres are subjected to forces in three axes…
- Longitudinal forces (X axis) under acceleration and braking. This simply necessitates a knowledge of the power-related constraints.
- Vertical forces (Z axis), in other words the weight of the car and any aerodynamic loads that are applied. Vertical forces apply when the car is both at a standstill (weight only) and in movement. Aerodynamic downforce is zero when the car is at a standstill but can represent as much as twice the car’s weight at speeds in excess of 300kph.
- Lateral forces (Y) which come into effect when cornering. They vary as a function of aerodynamic downforce and available grip.
Once these forces have been analysed, our experience enables us to establish tyre sizes and air pressures.
The tyre’s true design phase really begins after this groundwork and this is when the key technology-related decisions are made. This is the moment when any innovations see the light of day.
All tyres comprise four fundamental elements…
- Their construction. This is the tyre’s ‘frame’ and provides engineers with a host of possible configurations. Its form and the materials employed are the two chief parameters on which the developers can act. For example, even a small change in the angle at which the crown ply is laid can lead to noticeable differences in performance. The drivers are frequently able to detect construction changes thanks to the feedback they pick up from their car.
- The materials employed, both for the construction and the tyre’s tread and side walls.
- The profile of the tyre can be more or less flat or rounded and has a direct influence on the contact patch between the tyre and the ground. This in turn influences tyre’s performance.
- The tread pattern (or lack of tread pattern in the case of slicks). Rain forms an obstacle between the tyre and the ground, so it needs to be sliced through in order for direct contact to be re-established. And that is the role of the tread pattern. A Full Wet endurance racing tyre can clear up to 120 litres of water every second! Despite this surprising figure, Michelin took the racing world by surprise when it introduced its new Hybrid tyre in 2012. Like a slick, it doesn’t have a tread pattern. Instead, it is designed to eliminate the need for intermediate tyres in damp or drying conditions. It is a true revolution!
[email protected] MEDIA INFORMATION Le Castellet, March 27-28, 2015 When designing a new tyre, or an evolution version of an existing tyre, we work on all four of these elements concurrently. It is effectively vital to comply with the MICHELIN Total Performance philosophy which entails moving forward at the same time in all the areas that influence the overall performance package, without making any compromises”.
It is by rigorously complying with this approach that Michelin has succeeded in developing the necessary technologies to combine safety, performance and longevity, all of which are as fundamental in endurance racing as they are in everyday motoring.
In association with its partners, Michelin has achieved remarkable results on the race track. In 2011, for example, Audi Sport won the Le Mans 24 Hours after quintuple stinting. That’s more than 750 kilometres at an average speed of 225kph on a single set of tyres. Michelin’s partners achieved the same prowess in 2014, despite a 15 percent reduction in the size and weight of its LM P1 tyres!
Our Hybrid tyres have helped some of our partners achieve exceptional performances, such as at last year’s 6 Hours of Silverstone where Toyota chose to fit one of its cars with Hybrid tyres when light rain started to fall. The team noted a difference of up to five seconds per lap compared with cars running on rain tyres as the track began to dry, yet it was too soon to switch to slicks. These Hybrid tyres, which replace the former intermediate patterns, are a genuine technological breakthrough.
This technology, which has been put through its paces in racing since 2012, has today been carried over to mass-produced Michelin road tyres. In May, Michelin will launch the MICHELIN CrossClimate which will benefit from advanced racing technology to deliver the safety and performance of a summer tyre combined with the qualities of a winter tyre.