It was same story for Mercedes, which was testing the latest-generation slicks at Paul Ricard, on the sun-kissed Cote d’Azur. Paul Ricard is also a high-tech track with sprinklers that can dampen the circuit, so when Mercedes next go there, from 20–22 September, it will be to try out the 2017 wet weather tyres. For now though the focus was on the slicks, with Pascal Wehrlein at the wheel: Manor’s race driver who is very much a product of the Mercedes driver academy and often used by the German manufacturer during tests.
The track tests being carried out with the wide 2017 tyres are known as ‘blind tests’. In other words, only Pirelli knows exactly what the structural and compound characteristics of each tyre set being used for each run, actually are. Drivers, however, are masters of technical sensitivity. They can understand the variations between compounds even if it’s not been explained to them; they somehow manage to sense the differences between one structure and the next. Individual lap times, along with the subjective feedback from the drivers, help to build up a technical picture that is invaluable for development work. While these tests are definitely blind, they are also mute as well: no technical details are issued by Pirelli or teams to the media. The only information that is shared is an overall snapshot of data, which Pirelli provides not only to the teams involved in these tests (Mercedes, Ferrari and Red Bull) but also to all the other teams as well. And this is with the obvious objective of ensuring that all teams have exactly the same information when it comes to creating their new 2017 cars.
These radical cars will have more than 20% extra downforce compared to current levels. It’s an increase that the modified 2015 mule cars obviously cannot guarantee to simulate entirely accurately, which adds an extra delicate element to this very complex development programme. The goal is to have 2017 cars that are on average more than five seconds faster per lap compared to 2015. This year we are on the whole seeing times that are already around two seconds a lap faster than last year. So the downforce increase, along with the new wider tyres, will probably result in a performance improvement that even goes beyond the original objective.
One final fact. We are seeing these new wider tyres, but by how much? The front tyre is now 60mm wider, going from 245 to 305 mm; while the rear grows by 80 mm, from 325 to 405 mm. Overall, the width increase is 25% compared to current levels, which applies to the intermediates and full wets as well as slicks. The new 2017 sizes for slick tyres are:
• 305/670-13 at the front
• 405/670-13 at the back
The new Cinturato intermediates will have a diameter of 675 mm while the Cinturato full wets will have a diameter of 680 mm. The rim size remains unchanged at 13 inches, for all tyres.
Here is the full test programme, including tests that have already taken place as well as forthcoming tests. There are three teams involved: Mercedes (MGP), Ferrari (FER) and Red Bull (RBR).