The Chinese Grand Prix at Shanghai, where the P Zero White medium and P Zero Yellow soft tires will be used, is a race that has been traditionally been dominated by strategy. Even using several different strategies, drivers have often ended the race in close formation, setting up a thrilling finish. With a smooth surface and some sweeping corners – including the banked Turn 13 – this versatile tire combination is well suited to the varied demands of the Shanghai circuit.
Paul Hembery, Pirelli motorsport director: “With this being the third race featuring the combination of medium and soft this year, coming shortly after the Bahrain test, the teams are beginning to accumulate more knowledge of how our tires work with the complex 2014-specification cars. As a result, tire strategy is starting to become a bigger factor in the races.
China is a circuit that has showcased the effectiveness of a good tire strategy in the past, so the teams will be hoping to put their data from the first part of the season to good use and explore some of the strategy options available with our latest-generation P Zero tires. We’ve seen changeable weather at Shanghai before, so as always the ability to assimilate information quickly according to changing circumstances will be the key to getting the most out of them.”
Tires are allocated to the teams randomly with the help of a bar code, a process carried out by the FIA: the sport’s governing body. The barcode is the tire’s ‘passport’, which is embedded firmly into the structure during the vulcanization process and cannot be swapped. The code contains all the details of each tire, making it traceable throughout the race weekend with Pirelli’s RTS (Racing tire System) software. The FIA receives a list of the bar codes and then allocates each bar code – and therefore each tire – to every team at random. Pirelli itself is not involved in this process at all, meaning that the Italian firm cannot influence which tires are allocated to which teams – although a rigorous quality control process ensures that all the tires leaving the factory are entirely identical. Once at the circuit, the tires are then distributed to the teams in strict compliance with the list that has been previously prepared by the FIA. The bar codes allow both the FIA and Pirelli to ensure that the right teams, according to the regulations, are using the correct tires.
The circuit from a tire point of view:
There are a number of fast corners that the drivers accelerate through in Shanghai, meaning that they can make the most of the extra torque this year. In particular, turns 3-4, 7-8, and 12-13 require progressive acceleration but it is also important to have the right engine map in order not to experience too much wheelspin and damage the tires.
The high levels of downforce used in China mean high speeds through the corners, with forces that can exceed 3.8g. The softer tires are subjected to greater cornering forces as they generate more grip. Around 80% of the lap is spent cornering.
The Shanghai circuit features a number of long straights, which have an effect on the tires. The straights actually cool the tires down, meaning they have to get back up temperature quickly for the corners that follow.
The P Zero White medium is a low working range compound, while the P Zero Yellow soft is a high working range compound. This pairing ensures the capability to work effectively under a wide range of conditions: one reason why the combination has proved to be so effective this year.
China is the most demanding circuit on brakes of the entire year, with the new brake by wire system also having an effect on the tires. The tires are subjected to braking forces in Shanghai that peak at 4.3g.
Last year, Fernando Alonso won the race for Ferrari with a three-stop strategy, starting from third on the grid with the soft tire, then completing three stints on the medium tire. Jenson Button finished fifth for McLaren with a two-stop strategy.