Isola: Teams struggle to understand the C6 Pirelli tyre

Pirelli introduced its sixth tyre compound this season, the C6, with the hope that it will become the de facto qualifying tyre while also pushing teams for two or more pit stops given the 2025 tyres were designed with less thermal degradation based on feedback from drivers back in 2024.

But as it appears for now, the plan hasn't really worked for Pirelli, as the C6 has been close to the C5 in performance since its introduction at the Emilia Romagna Grand Prix, where some drivers used the C5 to post their fastest laps in qualifying.

The same happened in Canada a week ago, as George Russell and Max Verstappen used the C5 tyre to post the top two times in qualifying.

But Isola insists there is nothing wrong with the tyre but the teams and drivers just do not understand yet how to extract the best performance out of it.

"I would say that the [C6] compound was doing its job," Isola said. "Especially in Canada, we had a very good qualifying, in my opinion.

"The C6 is very close to the C5, but it is different in terms of behavior. Teams struggle to understand completely the C6. They know much better the C5—the C5 is giving more confidence to the driver.

"But the performance of the C6 is slightly better. If you are able to find the peak of performance of the C6, you get an advantage. Sometimes it is difficult," he explained.

Speaking further of Canada, the Italian said: "In Canada some teams and drivers preferred to use the C5 in qualifying because they felt more comfortable with the C5.

"But that created a different situation, and also the fact that the teams came to the race with more medium and more hard.

“Because usually when they have to use only the soft in quali, that means they have to choose between having one hard [set] and two mediums, or two hard and one medium. And this is not giving them full flexibility of strategy if they want to use hard and medium in the race.

“While in Canada, thanks to the fact that some of them qualified on the medium, they brought the medium to the race. And we had different strategies," he pointed out.

Pirelli had an initial plan of running the C6 tyre in Singapore, but Isola now revealed that this plan was revisited; he added: "As usual, we will simulate and find which is the selection that is giving the highest number of strategies in a small delta of total race time.

“Not sure if we are still on the idea to use it in Singapore, because Singapore sometimes can be a bit more aggressive. So let's see if we want to use it in Singapore. There is still a possibility for Vegas, where it is very cold."

The C6 will stay around for 2026, as Pirelli is keen on having six compounds to promote diversified strategies, but Isola set some development targets for his company's softest compound.

He said: "What I would like for the future is a C6 with more gap to the C5. So now it is around two tenths of a second; we need to have at least half a second.

"So even more aggressive with a level of degradation that is similar to what we have now to generate different strategies. For next year, we are working on a C6 with this target," Isola concluded.

(Quotes from Motorsport.com)