Le Mans pit laneNew regulations introduced by the ACO this year to slow tire changes are causing confusion at the 24 Hours of Le Mans.

The rules state that only two mechanics and one wheelgun are allowed to perform tire changes. But, during the first practice session yesterday evening, it became clear that not all of the competitors and invigilators had grasped the potential interpretations of the new rules. It is permissible to have more mechanics and equipment ready for action – provided that no more than two people and one wheelgun are in the "box" at once.

"It will be easy for us because we're used to working like that," said ORECA group CEO Hughes de Chaunac. "For newer teams, it will be more difficult. Also, the interpretation of the tire change is special because you can have in your mind two paths, probably.

"We will use six people, two by two by two: two people to change the rear tires, two more for the front left and another two for the front right. We have checked and we know we are right. The change will take around 22 seconds instead of 28-30 seconds."

"We have three wheelguns, but only have one in the box at once," said Risi Competizione technical director Rick Mayer. "We had a marshal yesterday who said we couldn't do that, so we had a big argument.

"There's going to be a lot more of that, no question. They change marshals every four hours, so with six marshals per car that's about 330 marshals in the pitlane and you've got to figure that some of them haven't got to grips with the new rules.

"We're going to speak to every new marshal we get and tell them our procedures so they know exactly what we're going to do – and we're going to do that every four hours, otherwise it'll just be a complete disaster."