This is how you should calculate your pitstops: Pitted every 9 minutes in the a-main. After the 45 min final, I had to drive nearly one more lap (34 sec), and then drive into the pit. Stopped the engine and checked the fuel left in the tank... Well... there was still some left in the fuel line... During the quals I calculated the mileage to be between 9.46 and 9.58... Proved to be right.