I'm trying to build up some endurance pace, but... At lemans in LMP2 Oreca07, the first 6-8 laps it drives perfectly. After 8-10 laps I'm having trouble keeping up the pace due to the car becomes more unstable. The rear have a higher tendensy to loose grip in turns. After 8-10 laps it has 87% tirewear left. I'ts medium tires, about 60-70 degrees in temps, with 2.0 bars. Im driving with P3 on rearwing. Moving the brakebias during race to adress less fuel weight, have less than little effect. After pit refueling its keeps being unstable. Is it the rubber in the racing line thats gets slippery? Are the tires done after 10%? should I drive with a higher rear downforce to begin with to handle this later rear unstability? other suggestions?