The 6 Hours of Circuit of the Americas (COTA) in Austin, Texas, USA, is the first non-European round of the 2015 FIA World Endurance Championship. It is particularly hard on tyres, especially since its surface – unlike Silverstone – is quite abrasive and the Texan weather at this time of year can be extremely hot, with track temperatures in excess of 40° C.

So, for the first time this season, Michelin’s partners will be able to use tyres designed for the high temperatures expected in Austin, including a ‘soft hot weather +’ solution for the LMP1 prototypes.

“We have analysed how our tyres performed at the last two 6 Hours of Circuit of the Americas races and that data has allowed us to develop tyres which are suited to the track’s specific demands,” says Jérôme Mondain, manager of Michelin’s FIA WEC programme. “It is important to remember, though, that the asphalt is quite recent, so it still has a tendency to evolve in terms of the amount of grip it provides.”

The combination of slow turns, the very high torque levels delivered by the hybrid power units of the LMP1 cars and the frequent re-acceleration out of corners causes tyres to heat up particularly quickly. As a consequence, Michelin has developed its ‘soft hot weather +’ tyre to carefully contain temperature build-up, with no detriment to either performance or longevity. The latter is especially difficult to achieve since it is customarily antagonistic with the temperature parameter, wear being one of the simplest means to clear heat build-up.

Are different tyre strategies possible?

At this season’s earlier six-hour races at Spa-Francorchamps (May) and the Nürburgring (August), Michelin’s solutions enabled the French firm’s partners to adopt varying tyre strategies which had a decisive influence on the final outcome in Belgium and Germany. At Spa, Audi Sport took full advantage of the potential of its Michelin tyres to begin double stinting before Porsche Team and thereby go on to win the race. At the Nürburgring, Porsche took revenge over its Ingolstadt-based rival to collect a one-two finish thanks to a strategy which capitalised on the durability of its tyres.

“The Circuit of the Americas is a tough challenge. It is effectively hard to multi-stint but we are confident in the potential of our ‘soft hot weather +’ tyre. This year, it will be important to take into account the fact that the LM P1 prototypes will only be able to use six sets of tyres for the race, and that might prompt some teams to try different strategies based on how they use the different solutions at their disposal,” notes Jérôme Mondain.

MICHELIN’s tyres for the 2015 6 Hours of Circuit of the Americas, by class:

LMP1

  • Slicks = choice between ‘soft high temperature’ and ‘soft hot weather +’ tyres
  • Hybrids
  • Wets

LM GTE Pro and Am

  • Slicks = choice between ‘medium low temperature’ and ‘medium’ tyres
  • Wet weather = choice between tyres for drying conditions and full wets

Michelin is bringing 2,300 tyres to the Circuit of the Americas for its WEC partner’s 23 cars.