Advertisement: Michelin at Le Mans 2015

Michelin
Advertisement
Subscriptions & booklets

B The official pre-test now offers the last opportunity LMP1, LMP2 and GTE cars to match the special features of the 13.629 kilometer 'Circuit des 24 heures'. Above all, this means fine-tuning the chassis and aerodynamics so that the racing tires can make the most of their potential. Because they have to withstand immense loads, especially on the hybrid prototypes of the LMP1 factory teams.

The legend writes a new chapter every year in June and casts its shadow far ahead: the 24 Hours of Le Mans are undisputed The highlight of every sports car and sports prototype season. Manufacturers, teams and tire partners usually work for almost twelve months towards the motorsport festival in the French department of Sarthe, which attracts great attention worldwide - from Japan to the USA and from Finland to New Zealand.

At the same time, Le Mans is also the absolute highlight within the long-distance world championship WEC (World Endurance Championship). For participants who have serious hopes for overall or class victory, multiple 24- or even 30-hour attempts count as good form of serious preparation.

The only problem: The special conditions at Le Mans cannot be reproduced anywhere - the characteristic mix of perfectly flat racetrack asphalt and undulating country roads, technically demanding passages, rapid alternating curves and absolute top speed sections is unique. The racing cars accelerate five times per lap, in some cases well over 300 km /h. This is also the reason why the official test day in Le Mans - traditionally carried out on the Sunday a good two weeks before the actual marathon - is of such great importance.

LMP1 hybrid racing cars as strong as an ox demand everything from their tires

The racing tires, especially on the hybridized Le Mans prototypes from Audi, Porsche, Toyota and newcomers Nissan - all four rely on the experience and competence of Michelin - really have to work hard.

In contrast to Formula 1 racing cars, for example, the LMP1 flounders roll on 18-inch tires with correspondingly slim flanks, i.e. with a dimension that is also used for sporty series models and which allows much more specific conclusions for the transfer of knowledge between the racetrack and road use.

In addition: With a width of 310 millimetersThe LMP1 tires of the Audi R18 e-tron quattro, Porsche 919 Hybrid and Toyota TS040 Hybrid are the same size on the front and rear axles. The new Nissan alone is an exception in this regard, but this has to do with its unconventional front-wheel drive concept.

The performance with which the at least 870 kilogram prototypes come up is hardly inferior to that of the Grand Prix class. This is also due to the enormous drive power that they pass on to their tires. The combustion engines already provide well over 500 hp in some cases - Audi, for example, specifies more than 558 hp for the 4.0 liter V6 turbo diesel of the R18 e-tron quattro.

Added to this is the energy that the - or the - hybrid system (s) contribute temporarily. Porsche was the first works team to arrive in the top class for recuperation. This means: per Le Mans lap, the 919 Hybrid with its combination of kinetic and thermodynamic energy recovery can store eight megajoules and invest in propulsion again.

This corresponds to an extra boost of more than 400 hp, which then drives the front wheels and temporarily transforms the Porsche into an all-wheel drive. Same picture at Toyota: The factory team of the Japanese brand based in Cologne-Marsdorf speaks of a total drive power of over 1,000 hp for the TS040 Hybrid.

Michelin racing tires deliver performance over more than 750 kilometers

Of course, this also puts the Michelin tires under enormous stress, because they have to bring this brute force safely and persistently onto the road - sometimes over astonishing distances. Especially in the cooler night, when the fastest lap times are being driven at Le Mans and the decision is often made to win or lose, the teams reduce the number of driver and tire changes for tactical reasons.

Background: According to the regulations, refueling and the exchange of tires may not take place at the same time, and the relay handover between the pilots also takes longer than refueling. It happens that individual drivers sit behind the wheel for up to four stints in a row - a record is even five stints. This corresponds to an operating time of a good four hours and racing distances of more than 750 kilometers at an average speed of 225 km /h ...

At the same time, the driving dynamics demand everything from the tires. LMP1 prototypes can not only accelerate rapidly, but are also extremely fast in corners. The centrifugal forces reach 3.5g and more, with a force of over 10,000 N (Newtons) acting on the tires. A similar picture emerges during the deceleration phases, in which up to 7,000 N press on the tires.

The power of the wind: At At full speed, the contact area doubles

Speaking of pushing: expertsexpect top speeds of 350 km /h and more for this year's '24 hours'. It is true that the Le Mans prototypes at the Sarthe come with a so-called 'low downforce' set-up, which gives preference to lower air resistance and thus higher speed when driving straight ahead over maximum aerodynamic downforce. Nevertheless, the racing cars are still pressed onto the road with great force at full speed. The wheel load - i.e. the weight that acts vertically on the tire - can double the tire contact area with it.

It doesn't get any easier when precipitation creates additional tension. Here too, Michelin is well prepared. The so-called hybrid tire from the French premium brand has been astonishing on wet slopes since 2012: it looks like a treadless slick, but thanks to a special construction and a particularly soft tread compound, this tire is characterized by outstanding performance in mixed conditions. If it pours from a full can, the 'wet' or even the 'full wet' tires are used. In extreme cases, the latter can get up to 120 liters of water per second out of the way.

Michelin LMP1 racing tires 2015: Narrower but more powerful

Compared to last year, the technologically highly demanding Le Mans -Prototypes made a significant leap in performance. This was reflected, for example, in the second round of the WEC season, the 6 Hours of Spa-Francorchamps, in a good six seconds faster lap times. And this, although the LMP1 racing tires from Michelin have to be between five and six centimeters narrower than in 2014. This also enabled the brand to reduce the weight per tire by around two to a good twelve kilograms.

News, background information, results on the current Michelin Le Mans website

Current news, videos and background information about the commitment From Michelin in endurance sport, the website>> lemanslive.com . The German-language website takes a look behind the scenes of the endurance world championship, reports from other endurance series, is live on site at the most important 24-hour races - and is therefore an indispensable source of information for true fans of this spectacular sport.

0 Comments

Leave a reply

Name *