How Pirelli is testing 2026 F1 tyres without 2026 cars

Pirelli has entered the subsequent stage of getting ready its smaller tyres for the 2026 Method 1 season, with Ferrari and McLaren testing its tougher compounds in Barcelona this week.

A lot of attention has gone to Lewis Hamilton continuing his preparations with his new Italian employer alongside team-mate Charles Leclerc and McLaren’s Lando Norris, nevertheless it can’t be pressured sufficient that lap occasions from the two-day check on the Circuit de Barcelona-Catalunya are totally meaningless – closely relying on the run programmes requested by Pirelli to check its smaller prototype tyres for 2026 and its compounds on the tougher finish of the size.

Whereas Hamilton can have benefited from extra seat time in a Ferrari from final yr, with the most recent procedures, steering wheel, Ferrari energy unit and so forth, the largest benefactor from the check is Pirelli itself. The Italian tyre producer is up in opposition to it to check and produce tyres which are narrower – 25mm on the entrance and 30mm on the rear – and smaller in diameter, from 720mm to 705mm-710mm entrance to rear, for use on vastly completely different vehicles subsequent yr.

The issue for Pirelli is that it has no consultant vehicles to check its new rubber on because the 2026 vehicles function considerably diminished drag and fewer downforce generated by the ground and diffuser.

Preliminary plans to cut back total downforce by 40 % have been watered all the way down to round 15 % following considerations over slower lap occasions, which at the moment are anticipated to be extra in step with present efficiency ranges. However the brand new technology of vehicles are considerably completely different in how and the place they generate efficiency, so Pirelli has to depend on the imperfect resolution of mule vehicles – equipment from 2022-2024 with trimmed wings – to gather real-life knowledge from its new rubber.

Following an preliminary check with Aston Martin in September – in its 2022 mannequin – and up to date wet-compound operating at Le Castellet, Ferrari and McLaren carried out work in Barcelona in more moderen vehicles with considerably decrease wing ranges, showing with absolutely flat mainplanes extra akin to one thing one would see in Baku or Las Vegas quite than on the high-downforce Montmelo circuit.

The general downforce ranges of those mule vehicles can be comparatively near the start-of-2026 specs, however as a result of the vehicles are so completely different it’s nonetheless troublesome for Pirelli to appropriately reproduce the masses its tyres can be subjected to. It’s due to this fact counting on being commonly fed simulations from groups to remain forward of the curve.

“The primary assessments had been primarily devoted to know how the mule vehicles are working, as a result of clearly they’re completely different,” Pirelli’s motorsport chief Mario Isola instructed Autosport. “The one factor we are able to do is to constantly ask for up to date 2026 simulations from the groups, mainly. We should replace our know-how and replace our development in line with the information that we obtain.

“We can’t simply depend on the mule vehicles as a result of it gained’t be wise, and we’ll proceed to supply them a digital mannequin of the tyre to make use of of their simulators and so they come again to us with their suggestions. And that is the precise path we must always proceed in.”

Each lowering downforce total and altering how it’s generated can have a serious affect on the character of the masses 2026’s smaller tyres are going to be subjected to. For Pirelli it’s due to this fact essential to get the inner development of its new tyres in the precise ballpark. Any additional fine-tuning can then be accomplished via tweaking the compounds.

The Italians are usually not simply taking anticipated 2026 efficiency under consideration, as F1 squads at all times have a tendency to search out speedy good points initially of a rules cycle, and Pirelli due to this fact has to have sufficient headroom to account for greater tyre hundreds additional down the road.

One necessary problem added to the combination is the upcoming X-mode, a DRS-like type of energetic aerodynamics which adjustments the angle of the entrance and rear wings on the straights for greater high speeds, versus the usual configuration which is dubbed Z-mode.

“We can’t generate these downforce ranges with the X-mode and Z-mode, it’s unimaginable,” Isola defined. “So, we now have to know what the perfect compromise for testing is and once we attempt to correlate the information from simulations with knowledge collected on observe. Step one is to outline the profile and development. From the check we had with Aston Martin we now have a very good place to begin, I might say. Compound growth is the second step.

Mario Isola, Racing Supervisor, Pirelli Motorsport

Photograph by: Mark Sutton / Motorsport Photos

“We all know that it’s a problem, as a result of in any case groups don’t need to lose any efficiency in comparison with the present vehicles, and the tyres are smaller, with decrease loading capability and so forth. We’re additionally once more testing new supplies and new concepts with a view to have a tyre that’s not heavier however nonetheless capable of maintain the load and to maintain the identical efficiency that the present tyres have.”

It’s not the primary time Pirelli has been chasing a shifting goal with one hand tied behind its again. However Isola identified the problem for 2026 was maybe barely simpler than in 2017, when F1 moved to larger and wider vehicles with far more downforce, which on the time was unimaginable to duplicate with a mule automotive. F1’s transfer to ground-effect based mostly vehicles for 2022 was additionally a difficult proposition.

“This can be a very comparable state of affairs to what we had for 2017 and 2022 once we needed to develop a whole new tyre for an entire new automotive, so it is not one thing new to us,” Isola stated in an earlier roundtable.

“In 2016 it was tremendous troublesome as a result of it was anticipated to have vehicles with a lot greater downforce and the efficiency was 5 or 6 seconds faster than the earlier yr, so it was unimaginable to duplicate this sort of efficiency.

“However the best way you obtain the load with the present vehicles is totally completely different in comparison with the brand new one, for instance. And on the straights, we now have numerous load now, whereas in 2026 at excessive pace we must always have much less load. So, the comparability is just not the identical.”