At Le Mans, tire strategy is a major engineering decision because a race lasts 24 hours and every pit stop costs time. Teams must balance grip, tire wear, fuel use, weather, driver comfort, and traffic. A fast car can lose the race if it changes tires too often or stays out too long on worn rubber.
The goal is to get the best total race time, not just the fastest single lap.
A stint is the period between pit stops, and endurance teams often run double or triple stints on one set of tires to save pit lane time. Fresh tires give more grip and shorter lap times, but changing them can add many seconds during a stop. Worn tires may be slower and risk overheating, sliding, or failure, so engineers track lap time loss, tread condition, and tire temperature.
The best strategy compares time saved in the pits with time lost on the track.
Key Facts
- Total race time = driving time + pit stop time + penalties
- Pit time saved by not changing tires = tire change time avoided
- Time lost on worn tires = lap time increase per lap x number of laps
- A tire double stint means using the same tire set for two fuel stints.
- Fresh tires usually increase cornering grip, braking performance, and driver confidence.
- A strategy is worthwhile if pit time saved is greater than extra lap time lost.
Vocabulary
- Stint
- A stint is the section of a race between two pit stops, usually limited by fuel, tires, or driver time rules.
- Double stint
- A double stint is when a team uses the same set of tires for two consecutive fuel runs.
- Degradation
- Degradation is the loss of tire performance over time due to wear, heat, and changes in rubber condition.
- Pit delta
- Pit delta is the total time lost by entering pit lane, stopping for service, and rejoining the track.
- Thermal window
- The thermal window is the tire temperature range where the rubber produces its best grip and wear rate.
Common Mistakes to Avoid
- Assuming fresh tires are always faster overall is wrong because the tire change may cost more time than the extra grip saves.
- Ignoring pit lane time is wrong because a slow stop or extra tire change can erase many laps of small speed gains.
- Treating tire wear as constant is wrong because degradation can change with temperature, fuel load, driving style, and traffic.
- Choosing a strategy from one lap time is wrong because endurance racing rewards the best average performance over many laps.
Practice Questions
- 1 A tire change adds 18 s to a pit stop. If staying on the same tires makes the car 0.6 s slower per lap for 24 laps, how much total time is lost on track, and is skipping the tire change faster?
- 2 A team can run either two single stints with tire changes or one double stint without changing tires at the middle stop. The tire change takes 20 s, and worn tires lose 0.4 s per lap for 32 laps. What is the net time gain or loss from the double stint?
- 3 A sudden cool weather change lowers track temperature and reduces tire overheating. Explain how this could change the decision to double stint tires at Le Mans.