Supercars outlaws natural tyre warming tactic from Darwin round

Changes to the operations manual have been made ahead of next week's Darwin Triple Crown, including the ban on warming tyres in the sun.

An updated Rule D17.1.16 now reads: "It is not permitted to use any device which artificially varies the temperature in or of a control tyre, regardless of whether the control tyre is mounted on a wheel or not".

And Rule 17.1.16.1 now reads: "Tyres are not permitted to be stored in direct sunlight, either in the paddock or in a team's garage".

A rule has also been created to clarify that tyres can only be stored in Dunlop Tyres' allocated service areas, a team's shade structure (which are set up alongside the transporters), or a team's garage.

The move is a response to what's informally known as 'baking' tyres to help lower real pressure without contravening the minimum pressure rules.

The issue is particularly prevalent at the Darwin and Townsville rounds, where high ambient temperatures allow teams to bake their tyres in the sun to increase live pressure and then bleed them back to a lower real pressure.

Will Brown, Erebus Motorsport Holden

Photo by: Edge Photographics

That changes the shape of the tyre and can decrease degradation, which was blamed on the underwhelming debut of the super soft compound in Darwin last year.

The changes will definitely be in place for the next two events, Darwin and Townsville, and could well be made permanent beyond that.

The minimum pressure has also been lifted for the Darwin and Townsville events. Teams will be required to have at least 20 psi of pressure in their super soft tyres, up from the standard minimum of 17 psi.

For the Northern Swing, Rule D17.1.17 states: "The minimum permitted pressure of a control tyre when fitted to a car is 20 psi which must be achieved at any time that the car is on the circuit during any session".