Pirelli’s race to develop 18-inch F1 tyres for 2022


F1 teams have begun testing 18in Pirelli tyres for next season. Adam Cooper looks at how 9 of the 10 teams are playing their part in developing the new low-profile rubber

Pirelli 18in tyre test Ferrari

Ferrari tested the 18in tyres last week in Bahrain

Pirelli via Twitter

In parallel to this year’s hectic Formula 1 race calendar a busy schedule of tyre testing activity is running throughout the season behind closed doors.

In conjunction with nine of the teams Pirelli is operating a test programme for the 18-inch tyres that are a key part of next year’s rule package.

Originally scheduled for this year until the pandemic hit, F1’s move to a low-profile format has been a long time coming, and it has in essence been pursued for marketing reasons.

Tyre companies believe that F1’s current tyre sizes have no relevance to their normal products. Michelin always insisted that it would only seriously contemplate a return to F1 if the sport went low-profile, while Pirelli also wanted to align its main motor sport activity with its road car range.

A team learns any time it runs a current car

It was no coincidence that when the Italian company recently announced a five-year industrial plan the second sentence was “centrality of high value confirmed with focus on tyres above 19-inches,” indicating what direction the overall business is taking.

For the F1 teams the new tyre size represents a huge change, thanks to the difference in the suspension characteristics of 18-inch tyres compared to their 13-inch predecessors.

On the plus side, for the 2022 and 2023 seasons, teams still have the use of tyre blankets – the move to outlaw them has been postponed until 2024, so they still have time to adapt to what will be a significant change to the way they operate their cars.

Pirelli 18in tyre test Alpine rear

Alpine testing in Bahrain last week with its mule car, converted to reflect 2022 regs

Pirelli via Twitter

This year’s testing programme, conducted with converted “mule” cars, is primarily for the teams to help Pirelli develop the new product. However it also gives their engineers and drivers a useful taste of what’s to come in 2022 while the new cars are still in development.

All teams were invited to participate, and nine agreed to do so, with only Williams opting out for cost and logistical reasons. Creating a mule car is not the work of a moment, as the tyres require substantial suspension modifications.

A total of 28 days of testing have been scheduled across the year, with six devoted to wet weather running.

The 22 dry days have been shared across the teams, with Mercedes, Red Bull, Ferrari and Alpine all running three days apiece, and McLaren, Aston Martin, Alfa Romeo, AlphaTauri and Haas getting two days each.

Ferrari had a day at Jerez in February, but all the other dry tests have been scheduled to follow race weekends, for ease of logistics – in the age of Covid restrictions it would make no sense to have trucks and personnel travelling round just for testing.

Related article

Ferrari and Alpine ran in Bahrain last week, while other race venues that will be used on the Tuesday/Wednesday after GPs are Imola (Mercedes), Barcelona (Alpine, Red Bull and Alfa), Spielberg (AlphaTauri), Silverstone (Red Bull, Aston Martin and Haas) and Budapest (Mercedes, McLaren and Ferrari).

The wet weather running (using sprinklers and tankers if the weather doesn’t cooperate) has been shared across three teams and three venues away from race weekends.

Ferrari ran two days at Jerez in February, and there will be two-day sessions for Mercedes at Paul Ricard in May (just after Monaco), and for Alpine at Magny-Cours in September (on the way home from the Italian GP).

All of this is of course at the mercy of Covid restrictions.

“Regarding the test plan that we have distributed, I’m confident that we can run most of them,” says Pirelli F1 boss Mario Isola.

“I’m not sure if we can run all of them. At the moment, we are confirming step-by-step. The reason why we have asked for more days compared to the usual 25 is to have flexibility. Because, again, nobody knows what is going to happen.”

Generally the teams have updated older machinery – Ferrari is using a 2019 model and Alpine a rebadged 2018 Renault – but some plan to convert their current cars.

Haas for example doesn’t have the resources to run an older spec car and Ferrari engine just for a two-day tyre test, while having switched from Renault McLaren can only run with Mercedes power, and is thus committed to using its 2021 chassis for the testing.

Pirelli 18in tyre test Alpine front

Alpine’s mule car was the 2018 Renault in its previous life

Pirelli via Twitter

A team learns any time it runs a current car, and it could be argued that even with an 18-inch conversion kit fitted those using 2021 models might gain more useful knowledge than those using older models. However, for Pirelli the age of the chassis used makes no difference.

“What is important is that the mule car is representative of the cars we will have in 2022,” says Isola. “The cars that we will have in 2022 will be heavier, with a different weight distribution, with some characteristics that are independent from the fact that you use a 2018, 2019, 2020 or 2021 car.

“It is important that when they prepare the mule car the characteristics are in line with what we will have in 2022, that’s why we are working together with the teams in order to understand how representative the cars are because.

“Thanks to the fact that now technical regulations are defined we can check if the performance, the level of downforce, and all the other elements are in line with the expectation.”

The other key part of the 18-inch equation are the wind tunnel tyres supplied to the teams, and which have to accurately reflect the behaviour of the real thing in terms of deflection and so on. That is hugely important given the wholesale changes to the aero rules for 2022 and the fact that teams are already hard at work on aero testing.

As the full-size 18-inch product has not yet been fully defined teams are not working with the final versions of the tunnel tyres, and thus there will be upgrades in the coming months.

2021 Formula 2 car

This year’s new F2 rims: 18in tyres were introduced for the 2021 season

Getty Images

One small advantage for Pirelli is that AlphaTauri has finally switched from a 50% scale wind tunnel to the 60% format used by everyone else – until now Pirelli’s engineers had to create the smaller size tyres just for the Italian team, which was an extra headache.

“As usual when we have a complete new product we upgrade the version of the wind tunnel tyre,” says Isola. “We are proceeding in parallel, because the construction for the 18 inches tyre is not frozen.

“So we work in parallel also with a wind tunnel tyre and rig test tyres that are the full version of let’s say non-competition tyres that we supply. And we get feedback from the teams, because they use them in the wind tunnel.

“So they can tell us which is the level of accuracy, and if we need to make any modification. The system is the one that was implemented some years ago, especially in 2017 when we had to develop the wider tyres. The system is working well. So we will continue like that.

“It is much more challenging compared to any changing of construction we have done with 13-inch tyres. On the 18-inch tyres it is a completely new product and a lot more difficult, so for sure the first version [of the tunnel tyres] needs to be updated.

“And we will work in order to give a better product to the teams, and step-by-step I’m sure that we can converge to a product that is very, very close to the real tyre. That is exactly what we have now for 13-inch tyres.”

The change of sizes has required a huge R&D investment from Pirelli, and that in turn has led to a change in the length of the company’s current contract.

Related article

The last FIA tyre tender it won covered the four seasons from 2020-2023, with the first to be run with 13-inches followed by three with the new sizes.

When the introduction of the new regulations was postponed by a year it meant that Pirelli would only have two seasons with the revised size.

That anomaly has now been addressed by the FIA and F1, with 2025 added to the contract to give Pirelli a full three-year term with 18-inch tyres before it has to enter another tender process and potentially lose out to a rival bidder.

“That was a discussion that started last year when it was clear that we had to move the introduction of the 18-inch tyres to 2022,” says Isola.

“So we had this discussion, there was a proposal to continue, and we accepted the proposal. We have a big investment in money and development with the 18-inch tyres, and obviously, having the possibility to use them for three years is I believe the correct approach.

“And that’s why in the last tender we had this four-years agreement, including one year with 13-inch, and three years with 18-inches. So it’s an effect of the Covid, I would say.

“It was decided to keep this three-year agreement on 18-inches and therefore to extend by one year. We are obviously happy that we can develop the 18-inch tyres and continue and use them for three years, considering that is the investment that is behind this new product.”

So how do the 18-inch rims and tyres look, given that this was done for marketing and PR reasons?

As with any rule changes, one soon gets used to them, and they don’t look out of place on F2 cars, which already adopted the new size in 2020.

In truth we’ll only see the real picture when they are fully integrated into the 2022 F1 models in conjunction with the substantially different bodywork that the new rules mandate.