F1 changes rule to make sure teams aren't cheating on tire pressures
The FIA has continued its quest to control tire pressures by announcing that henceforth they will be measured before the wheels are put on the car.
Until now the measurements have been made with the wheels on the car. However, the suspicion is that some teams have gained an advantage by pre-heating the hub/brake assemblies which in turn instantly heats up the tires and pushes up pressures.
Under this suspicion, teams can fit tires with lower initial pressures than the prescribed minimum which then appear to be legal once heated up – but when the car goes out on track the hubs cool down and tire pressures drop to a lower level that enhances the car's performance.
A note to teams from the FIA's Charlie Whiting said that for practice and qualifying: “With immediate effect the minimum starting tire pressures, as set out in the Pirelli Preview for each Event, will always be checked before the wheels are fitted to the car.
“These checks will only be carried out on new tires or used tires from a previous session, they must be done in the presence of, and be verified by, your designated Pirelli engineer. Once set no air may be released from the tires but air may be added, in addition, if a set of tires is used more than once in any session there will be no requirement to reset the pressures to the minimum starting pressure.”
In addition, there is a new procedure for the grid: “Again the starting pressures will be checked before the wheels are fitted to the car. These checks must be carried out in the presence of, and be verified by, a scrutineer, an FIA delegate or your designated Pirelli engineer. Once set no air may be released from the tires but air may be added.”
A further step on regulating tire pressures will be tried out at the Silverstone test. Usually teams heat their tires in blankets at a set temperature for several hours, before “boosting” them with a higher temperature, typically in the last 30 minutes before the tires go on the car, based on prescriptions provided by Pirelli.
At the instigation of Pirelli, the plan is for tires to be heated at a constant temperature before use, without the extra boosting. Teams suggested that this should be tried at a test, rather than race weekend, so that the FIA could be provided with data on what impact the change had.
