Following the debacle that put the Lewis Hamilton’s race victory at the Italian GP into doubt, the FIA are now working with Pirelli to regulate on a set of procedures to ensure the teams are running minimum tyres pressures.
We must remember that tyres running at lower pressures are more vulnerable to cuts from debris and kerbs. Tyres operating at lower pressures also can give incremental grip and mitigate blistering.
TJ13’s very own Mattpt55 has educated the team that given a starting tyre pressure and temperature – and change in tyre pressure resulting from a temperature alteration, is entirely predictable and the result of a mathematic algorithm. Something to do with PV=NRT… maybe.
Currently, the tyre blankets heat the tyres to a maximum temperature of 110 degress, although the operating temperature band for the various tyres during the race is mostly between 120-140 degrees.
In Monza, as the tyres were mounted on Rosberg’s car at the required temperature by Pirelli, the tyre pressures were checked and agreed to be legal.
The problem, was that Mercedes decided not to continue to warm Rosberg’s tyres and disconnected the tyre blanket power. That said, if you watch the footage back, the blankets are only removed around 30 seconds before the parade lap begins – some 2 minutes after the test.
Tyre temperature reduces – and so does the pressure.
Paul Hembery was asked during the Italian GP weekend, whether the teams were complying with Pirelli’s new tyre pressure regulations. He replied, “Mainly”.
Pirelli are of course aware that teams manipulate tyre pressure by affecting temperature and the embedded Pirelli representatives in each team are privy to tyre data telemetry from the moment the parade lap begins.
Pirelli originally wanted a Psi minimum of more than 19.5 Psi for the rear tyres in Monza, however the teams talked them down to this level.
TJ13 has learned that Pirelli requested an incremental hike in Psi to cover the team’s ability to manipulate tyre pressure, including during the ‘blanket warming period’ on the grid prior to the start of the race AND after the tyre has been pressurised and agreed by Pirelli.
This would ensure the minimum Psi required by Pirelli is adhered to, even if the tyres are unheated from the 5 minute warning.
Consequently, the FIA and Pirelli’s solution to ‘on grid tyre pressure manipulation’ is simple.
The teams must be required to keep their tyres above a certain temperature prior to the 30 seconds before the parade lap. This means the Psi Pirelli require from the tyres up to 30 seconds before the cars begin to roll can be predicted.
Either that, or the teams will be forced accept a higher Psi minimum from Pirelli to allow for potential cooling of the tyres from when they are tested/filled by Pirelli at the required temperature.
Then again – this would surely be all too simple for the FIA to regulate.