What Pirelli’s 18-inch wheels change for F1’s designers
As part of this overhaul, the sport has finally adopted a larger wheel rim design, having flirted with the idea on many occasions in the past.
This shift to 18-inches means that Pirelli has also had to adapt its offering and will produce a tyre with a much shorter sidewall.
And it’s here where teams and drivers might have to adapt the most when we consider how the new tyres behave when compared with the outgoing rubber.
Firstly, the driver’s view will be more impaired than before. Not only have the wheel rims been increased in diameter, so has the entire assembly.
With Pirelli’s tyres mounted, they are 60mm taller than the previous generation, which will obviously make looking out over the top of them a little more challenging.
Plus, drivers’ sight will be hindered further still when we consider the wheel wake deflector that will be mounted above it.
The aerodynamicists will also find themselves challenged by the changes, as the lower profile tyre will behave differently to the outgoing rubber – with the dynamic behaviour of the tyre creating inconsistencies that they’ll be keen to get a handle on.
A number of aerodynamic tricks have been used in the sport’s recent past to try and mitigate the effect known as ‘tyre squirt’. But, with many of those design features either removed or heavily constrained, teams will have to find new ways to deal with the resultant change in the tyre’s stiffness and sidewall height.
Photo by: Giorgio Piola
Pirelli has long been at the mercy of the sport in order to increase the entertainment aspect, with thermal degradation identified as a way of creating strategic differences between the teams and drivers.
However, as part of the overhaul, the drivers had asked that there be less focus on this in order that they might be able to race more freely without fear of having to manage the tyres throughout the course of a race.
Driving well below the actual potential of the car became a common theme over the course of the last few years, in order that the tyre didn’t overheat and result in an extra pitstop than was originally planned.
All that was needed during a stint was for the driver to stick to a lap time delta that meant it was quicker to be out on older tyres than it was to lose time in the pitlane stopping for fresh tyres.
Also factor in any time loss for having to pass traffic or repass lapped cars and suddenly the tortoise-style strategy was much more appealing than being the flat-out hare.
Pirelli’s approach to the design of the new tyres and the impact of the redesign of the car could alter this strategy perception though.
The stiffer, shorter sidewall tyres will feature a new construction in an effort to resolve some of the temperature issues teams faced on the shoulder of the tyre, which should result in less management.
Teams worked hard during the previous era to alleviate some of these issues and found pockets of performance from numerous sources, whether it be their tyre blanket strategy, the design of the wheel rim, brake ducts or suspension setup.
All of these face a significant reset in terms of their design going into 2022, not forgetting that the aerodynamic balance of the car will also vary, given the shift to a more underfloor biased design.
Stacks of tyres in heated blankets
Photo by: Andrew Hone / Motorsport Images
First up, whilst the current regulations suggest that tyre blankets will finally be banned from 2024 onwards, the main change going into 2022 is that the maximum temperature of the blankets is set to be reduced from 100 to 70 degrees Centigrade.
This could have an impact on how drivers approach their exit from the pitlane or at the start of a race, as they might need to warm the tyres, rather than immediately manage their temperature.
However, the way the tyres are worked may differ in any case, as whilst many teams had raised the suspension elements and used more extreme pushrod-on-upright solutions in recent years to help with various aerodynamic endeavours, these, along with the hydraulic solutions that have helped with compliance, have been removed.
Mercedes AMG F1 W10 front suspension detail
Photo by: Giorgio Piola
Instead, teams will return to classically sprung suspension arrangements which obviously have a bearing on the car’s behaviour and provide the driver with different feedback and feeling.
Meanwhile, the switch to BBS as the sport’s single supplier of wheel rims means that any advantages that had been gained in terms of controlling the transfer of heat between the rim and tyre will be eroded too.
The likes of the large cooling fins seen on the Mercedes in recent years are no longer possible.
Mercedes F1 AMG W09 rim tyre
Photo by: Giorgio Piola
It’s also worth bearing in mind that the size of the brake discs are also different in 2022, with the standard 278mm diameter for front and rear discs used since 2017 exchanged for new dimensions.
At the front, teams can select a disc size between 325 and 330mm, whilst at the rear the allowable disc diameter will be between 275 and 280mm.
These changes obviously have ramifications in regards to the disc’s designs, and their proximity to the larger wheel rims, with additional design considerations then feeding back into the design of the brake duct too.
This could be considered an avenue where teams might be able to find some small gains over their rivals.
But whilst the ability to create the complex designs they used in the past has been dramatically curtailed, the transfer of the heat generated under braking might still prove pivotal in managing the tyres temperatures.
As we can see from McLaren’s design for its mule car, there’s scope to increase the brake drum to match the size of the wheel well, as it would have done previously.
However, the teams might also find there are some benefits to having a slightly smaller drum and an enlarged void between it and the wheel rim.
As anticipation builds for the 2022 season and we get our first sight of the cars, we’ll undoubtedly wax lyrical about the different aerodynamic approaches that teams have taken given the new regulations.
However, make no mistake, the teams and drivers will be hoping they’ve gotten things right when it comes to the aspects that can affect tyre performance.