Formula 1’s latest technical controversy has erupted at the Brazilian Grand Prix amid suspicions that some teams have allegedly used water to cool their tyres from the inside.
With the fight for the championship between Red Bull and McLaren getting closer, there has been an increased probing between the two squads over elements of their cars.
McLaren came under fire for its mini-DRS rear wing, which the team had to alter in the wake of complaints about the concept being outside the rules.
Then more recently there was a row over Red Bull having a front bib adjuster inside its car that some of its rivals suspected could have been used to adjust ride height during parc ferme conditions.
Both matters brought intervention from the FIA, but neither squad was found to have done anything illegal.
Now, however, Autosport has learned that attention has shifted to a trick that Red Bull suspects has been used by several of its rivals – believed to include McLaren – to help cool tyres during races.
The theory is that some teams have found a way to inject water – or another unspecified liquid – into the tyres through the valves shortly before tyres are fitted to the cars in the race.
Having such a coolant inside the tyre could help keep the bulk of the tyre cool to help limit thermal degradation, and ultimately help deliver better race pace.
It is understood that concern about the activity erupted after the Singapore Grand Prix when sources suggest some rims of teams were spotted with liquid inside them – something that is unusual.
That is because teams normally make an extra effort to try to remove all moisture from inside a tyre as that helps to ensure teams can hit perfect peak tyre pressure.
F1’s technical regulations make a point of trying to limit the amount of moisture that teams can remove rather than add.
Article 10.8.4 states that: “Tyres may only be inflated with air or nitrogen” and “any process the intent of which is to reduce the amount of moisture in the tyre and/or in its inflation gas is forbidden.”
Autosport has learned that the FIA has been alerted to the concerns about the activity, and its head of single-seater matters Nikolas Tombazis has been in dialogue with Pirelli and teams at the Brazilian GP to discuss the matter.
Furthermore, it is understood that Tombazis kept a close eye over the removal of the tyres from their rims after the sprint race in Brazil to see if there was any evidence of unusual liquid there.
Although there has been no official comments from the FIA over the matter, it is understood that there is scepticism about whether or not teams would be trying to exploit matters in this area.
The FIA scrutineering report from the sprint race also confirmed that tyres were inspected, and given the all clear. It said: "The tyres used by all drivers during the Sprint today have been checked."
It is understood that the idea of adding moisture to tyres has been outlawed for many years through a technical directive that the FIA issued previously, so anyone found to have been adding liquid in this manner could risk being reported to the stewards.
The race pace mystery
Red Bull has been hunting for answers as to why its race pace advantage over rivals disappeared this season – especially at the Miami GP where a number of other squads made a leap that could not be explained through upgrades.
Max Verstappen said ahead of the Brazilian GP that the long runs of rival teams are hard to fathom.
“Some teams made huge steps on race pace, which is quite odd,” he explained. “Because if you look at our car compared to last year, we made steps in qualifying and in the race.
“The others also make a decent step in qualifying pace, but then they make a much, much bigger step in race pace. And that's something that's hard for us to understand.”
Team principal Christian Horner told Autosport recently about the swing of form in Miami: “If one was a sceptic and somewhat paranoid, you say something's changed. Because even when we've gone back to the configuration of the car that, for example, we had in China, we still have some of the same issues that we have experienced.
“But, in saying that, it changed for everybody, potentially. But I've never in a season seen a swing so exaggerated. Obviously we have to get on top of that. We have to understand it.”
