[Here are the LeMans regulations in a .pdf file](https://assets.lemans.org/explorer/pdf/courses/2019/24-heures-du-mans/regulations/2019-24-heures-du-mans-supplementary-regulations.pdf)
They do make pit stops to swap tires and refuel.
In aerodynamics (looking at Newton’s laws of motion), drag is proportional to velocity squared.
The competing cars have a much lower drag coefficient than production cars, more efficient drive trains with less power loss and weight less than 900 Kilograms.
Latest Answers