Not for the first time before a regulation change, all eyes are on Mercedes. Toto Wolff’s team finds itself at the centre of a controversy that could define the 2026 season and the upcoming regulatory cycle.
Mercedes have managed to develop a solution that increases their engine compression ratio above the 16:1 limit.
For the sake of clarity, it must be emphasised the German squad’s engine still complies with this maximum ratio during static tests.
Their design, however, is understood to facilitate an increased compression ratio when the car is out on track. Via thermal expansion, Mercedes can attain a higher value – and by extension unlock more horsepower and performance.
Mercedes defend their technology
The Silver Arrows believe this interpretation of the regulations is legal. Indeed, Toto Wolff’s team communicated regularly with the FIA whilst they were working on their engines to ensure its conformity.
Until now, the FIA have given Mercedes the green light on their controversial trick. However, the last few weeks have understandably seen a growing opposition from other manufacturers.
Audi, Honda and Ferrari are adamant the German team’s trick to increase compression ratio – even if it passes stationary checks – should not be permitted.
Red Bull are known to have caught wind of this idea some time ago, courtesy of an engineer they signed from Mercedes. Crucially, though, the Milton Keynes outfit have not developed this technology to anywhere near the same extent as their German rivals.
Because of this, Red Bull are not expected to be particularly vocal in defending the legality of this compression ratio solution. After all, any benefit for the Mercedes engine will also extend to their customers teams – McLaren, Williams and Alpine.
This is the backdrop behind tomorrow’s meeting between the FIA and the teams. Whilst other matters will be discussed, none will compare to this contested engine row.
Based on the latest reports, the FIA are open to taking action on this loophole.
This is something that rival manufacturers are set to make abundantly clear in their next meeting.
