Red Bull’s decisive move: How a majority vote could force new F1 engine rules on Mercedes. The FIA will start “hot” compression tests on Mercedes engines from the Australian GP.

Engine controversy: Mercedes on the ropes as hot compression measurements are set to start in Australia, and regulatory approval won’t require unanimity. The FIA is keeping its commitment to clarify a matter that has sparked significant debate.

Red Bull’s position will be decisive

As we highlighted last weekend, this week proved to be very important regarding the Mercedes engine case, and the two meetings held appear to have brought notable developments.

According to Corriere dello Sport, the FIA has decided to change how the compression ratio measurements are conducted. Under the initial version of the regulations, these checks were to be performed cold. Starting from the Australian Grand Prix, however, the tests will be carried out ‘hot’ by heating the V6 engine components while static. The FIA agreed to revise the measurement criteria following the clarification letter sent months ago by Ferrari, Audi, and Honda.

Moreover, introducing this change to the regulations will not require unanimity. Instead, a qualified majority will suffice, composed of the FIA, Formula 1 management, and four of the five engine manufacturers. This makes Red Bull’s position decisive. Initially, Red Bull had remained neutral and did not sign the clarification letter sent by the other three engine manufacturers. However, the team’s stance now appears to have shifted, creating the conditions for the qualified majority needed to implement the new hot compression checks, still static but at operating temperature.

Enrico Gualtieri, Ferrari’s power unit director, had expressed full confidence in the FIA to resolve the issue before the start of the season during the presentation of the Ferrari SF-26. The Federation has kept its promise to clarify this gray area in the regulations, which had previously led to differing interpretations.

The shift toward more stringent “hot” engine verifications represents a significant victory for those seeking transparency ahead of the new regulatory era. With the political landscape shifting in favor of tighter controls, the Australian Grand Prix will serve as the first true test of whether these technical clarifications will level the playing field for the 2026 Formula 1 season.