FIA clears 2026 engine solution: potential advantage for Mercedes and Red Bull examined. The FIA has approved a modified compression ratio solution for the 2026 F1 engines.

The debate surrounding the 2026 Formula 1 power units has officially begun, following the FIA’s decision to give Mercedes and Red Bull the green light to use a so-called “trick” in their engine design. With the governing body approving a modified compression ratio for their respective power units, the issue has quickly turned into a full-blown 2026 engine case, raising questions about how much performance advantage the two manufacturers could gain over their rivals.

The FIA has effectively authorised Mercedes and Red Bull to run power units featuring a revised compression ratio, a technical solution that is considered fully compliant with the new 2026 regulations. This small but significant detail has already caused concern within the paddock, as the two manufacturers involved could benefit from a measurable performance gain compared to competitors who have chosen a different technical approach.

Ferrari, Honda and Audi are firmly opposed to the methods adopted by Mercedes, and presumably also by Red Bull. The Maranello-based team, in particular, wasted no time in making its position clear, formally expressing its disagreement in a letter sent directly to the FIA. From Ferrari’s perspective, the approval of this solution risks creating an uneven playing field ahead of a regulation cycle that is supposed to reset competitiveness across the grid.

But how much could Mercedes and Red Bull actually gain from this solution? According to several sources within the paddock, the potential advantage could be worth as much as 0.4 seconds per lap. If these estimates prove accurate, teams that do not use a Mercedes or Red Bull power unit would already find themselves at a disadvantage even before the 2026 regulations officially come into force, making the development race significantly more challenging.

From the FIA’s point of view, Mercedes is considered to be in full compliance with the technical guidelines outlined in the new regulations. The governing body has clarified that the loophole was first identified by the German manufacturer, which interpreted the rules in a way that allowed this specific compression solution. According to reports, the same concept was later adopted by Red Bull following the arrival of a former Mercedes employee within the team’s power unit structure.

Discontent among the teams continues to simmer, in what risks becoming not only a battle fought on track, but also one that plays out behind the scenes. The situation has the potential to strain relationships between engine manufacturers, especially at a time when cooperation and regulatory stability are seen as crucial for the long-term future of the sport.

The FIA has stated that it could consider further changes to the regulations or to the measurement methods in the future in order to address the concerns raised by rival manufacturers. However, any such intervention would only be possible from 2027 onwards. For the 2026 season, the compression solution used by Mercedes and Red Bull will remain legal, leaving other teams with no choice but to adapt and attempt to close the gap through their own development efforts. In any case, this is an issue that appears far from being resolved and is likely to remain a major talking point as the new era of Formula 1 approaches.