How much fuel load should the car carry during final qualifying as it has to use the remaining fuel load on the race day? Should the car make two or three pit stops instead of just one? This is what race strategists have to grapple with. For each pit-stop, the car loses thirty or so seconds. However, with more pit stops, the car can run significantly faster with a lower fuel load. Tyre changes used to play a strategic role in winning races, though this has become less significant with the introduction of a single tyre supplier in 2007 , which gives teams a narrower range of tyres to work with.