Ferrari has stepped into the growing debate around F1’s 2026 power unit rules, amid reports of Mercedes and Red Bull exploiting potential loopholes related to compression ratios. Scuderia technical director Loïc Serra weighed in on the “gray areas” that have dominated paddock talks.
The next F1 rules cycle will deliver the biggest technical reset since the start of the hybrid era. From 2026, power units will be split 50–50 between combustion and electric power. The MGU-H will disappear, and the FIA is pushing cars that are lighter, drag-reduced, and less dependent on downforce.
Alongside that reset, a question has emerged. Have some manufacturers found a legal interpretation advantage before the cars even touched the track? Serra gave his take on the issue, highlighting “gray areas,” which F1 has always seen during regulation changes.
“I think what we call ‘grey areas’ is nothing more than the creativity of human beings, thinking of things that have never been thought of before,” Serra told Motorsport.com. “I don’t think a new regulation, four years or one year after its introduction, changes the overall picture at all. It doesn’t change the framework. It changes the scope of exploration, because at the start of a new regulation everything is immature.”
History backs Serra’s comments, who moved to Ferrari from Mercedes. Brawn GP turned 2009 upside down with the double-deck diffuser. In 2014, Mercedes arrived with a package that rewrote the hybrid era, winning seven double titles.
Big resets create space. Those who interpret faster usually lead. This time, the discussion centers on the tightening of compression ratio limits. For 2026, the maximum ratio drops to 16.0, and critically, the regulation defines measurement at ambient, static conditions.
Rivals believe that internal parts could be designed to expand at operating temperatures, closing the gap inside the cylinder and effectively increasing real-world compression while staying within legal limits. That is where Mercedes and Red Bull are suspected of pushing their development. Serra pointed out that this process never really stops:
“It’s more likely to see big differences because the concepts haven’t converged yet. But look at this year. Look at 2025: you’ve seen gray areas. So many. To explore. People are thinking. Everyone thought: ‘There’s no margin.’ In reality, whether the Formula 1 regulations are stable or not, human creativity is limitless.”
“Every year, and not just every year, but every week, I get to see people come in with new ideas, and I say, ‘Oh, look, we thought of this, we thought of that.’ It’s fascinating, but, it happens everywhere.”
Mercedes will power its own team, along with McLaren, Williams, and Alpine. Red Bull, meanwhile, will use Red Bull Powertrains for the first time, supported by Ford. Ferrari will continue to power itself and Haas.
FIA approves changes as Ferrari shows concern over Mercedes and Red Bull’s compression ratios
The 2026 regulations also leave engineers room to explore. With electrical deployment playing a bigger role, teams now have more incentive than ever to squeeze every legal gain from the combustion side.
That is why rivals, like Ferrari, worry about heat-driven expansion in the engine. The rule did not specify how much movement at a certain temperature becomes unacceptable. If the piston is closer to the top of the cylinder while running, the real compression rises, and so could performance by up a second. The FIA addressed the situation as per reports:
“Mercedes and Red Bull Powertrains can proceed on their own terms. The FIA has admitted that the combustion chambers of their respective engines are legal if, during tests carried out at room temperature, a compression ratio of 16:1 is measured. It doesn’t matter if, when heated, the resulting value is higher.”
The governing body acknowledged the technical reality and the conversation it has triggered, but there is no immediate sign of intervention. Right now, it is unknown what the true advantage might be. Regardless, things will be clearer after pre-season testing in Barcelona.
Edited by Hitesh Nigam
