FIA to ban Mercedes engine “trick”? The 2026 compression ratio controversy explained. The FIA is set to decide on the controversial compression ratio in Formula 1.

Decisive days are ahead in Formula 1 as the FIA could make a final decision on the compression ratio once and for all, and a new rumor is already sending shockwaves through the paddock. As F1 prepares to return to action in Bahrain, the FIA may finally resolve the long-standing issue surrounding the compression ratio. The 2026 season has lived up to expectations, emerging as a “year zero” in which teams battle as fiercely off-track as they do on it.

The focus remains on the compression ratio under the new technical regulations, with Mercedes in the spotlight due to a potential loophole that could give them a massive advantage. Other engine manufacturers, led by Ferrari and followed by Audi, Honda, and now even Red Bull Ford, have launched a prolonged protest that may finally reach a conclusion.

Even among the drivers, opinions are divided. Lewis Hamilton and Max Verstappen have strongly criticized the new cars, while others prefer to remain cautious and avoid public comment.

As Formula 1 fires up again in Bahrain for the second and final week of pre-season testing, the FIA will meet with teams this Wednesday to decide the fate of the disputed technical regulations. According to renowned German magazine Blick, McLaren is requesting three technical changes, including a potential revision to the starting procedure.

The fury of Ferrari and others

Last week in Bahrain, cars conducted starting practice sessions, but the results were not all positive. In particular, Andrea Stella commented: “Our drivers complain that overtaking is even more difficult now! On top of that, having to lift off the throttle on the straights could catch the car behind by surprise, and we could witness a terrible accident.”

McLaren, of course, has no complaints about the Mercedes engine. In contrast, Ferrari, Honda, and Audi are furious. According to Blick, the three engine manufacturers claim that the FIA will ban increasing the compression ratio in the cylinder (from 16:1 to 18:1) for the eight cars running Mercedes power units, despite their homologation.

This change could be implemented before the Australian Grand Prix. If confirmed—but we will only know on Wednesday—it could dramatically shift the balance of power on the grid. Will Mercedes engines face a reduction in performance?