Mercedes team principal Toto Wolff has publicly appealed to the FIA to guarantee that the new regulations permitting power‑unit manufacturers to evolve their engines throughout the 2026 campaign do not upset the established competitive order in Formula 1. The latest rulebook for the 2026 season introduces a performance‑balancing provision designed to give teams that fall behind the leading engine supplier by a defined margin the chance to develop their power units. Under the new framework, the FIA has outlined three distinct windows for Additional Development and Upgrade Opportunities, abbreviated as ADUO, during the season. Any manufacturer whose internal‑combustion engine is judged to be at least two percent slower than the benchmark – currently the best‑performing unit – will be eligible for these development slots.
The intention, according to the governing body, is to level the playing field without allowing any team to overtake the frontrunners in a single leap. The sport’s regulator is expected to issue further clarification on how these provisions will be applied before the next round of racing in Miami, where Mercedes arrives as the clear leader after winning the opening three Grands Prix. Wolff, speaking earlier in the week, emphasized the delicate balance that the ADUO system must strike.
"The principle of the ADUO was to allow teams that were on the back foot in terms of the power unit to catch up, but not to leapfrog," he said. "It needs to be very clear that whatever decisions are being made, whichever team is granted ADUO, that any such decision may have a big impact on the performance picture and on the championship, if not done with absolute precision and clarity and transparency." He added that any form of gamesmanship would have no place in the process and that the FIA must act in the right spirit, ensuring that the integrity of the sport remains intact.
Mercedes' own power unit, built in-house, has set the benchmark for the season, and the team’s dominance suggests that other manufacturers may be granted the chance to close the gap. Wolff hinted that Honda, which currently supplies only Aston Martin, appears to be the sole power‑unit maker in genuine need of assistance.
"The teams will have their performance pictures and, as it seems for me, there's one engine manufacturer that has a problem and we need to help. And then all the others are pretty much in the same ballpark," he explained. "So, I would be very surprised, actually, and disappointed if ADUO decisions that were done would come up with any interferences into the competitive pecking order as it stands at the moment." Mercedes not only runs its own engines but also provides power units to three customer teams – McLaren, Alpine and Williams.
Ferrari, another works team, supplies Haas and the newly‑entered Cadillac. Red Bull, after years of partnership, has built its own power unit for the first time and now supplies its junior squad, Racing Bulls. Audi, meanwhile, operates as a works team without any customer outfits. Ferrari, the nearest challenger to Mercedes in the early standings, has welcomed the ADUO concept as a means to narrow the performance gap to the Silver Arrows.
Team principal Fred Vasseur has spoken about using the extra development windows to "close the gap" to Mercedes. When asked whether he feared that an ADUO grant to Ferrari could put Mercedes on the back foot later in the year, Wolff responded that he was not worried, but rather vigilant. "I think we are all monitoring how decisions are being made. And we have precise data from our own analytics of where we see engine performance of our competitors and ourselves.
In that respect, I think the FIA is looking at the same data and the FIA certainly, I would very much hope that they continue to see themselves as protecting the integrity of the sport. Because you don't want to allow an ADUO to a team that suddenly leapfrogs someone. The ADUO was always meant as a catch‑up mechanism and not as a leapfrog mechanism," he said.
The upcoming Miami Grand Prix, scheduled for May 1‑3, will be the second Sprint weekend of the season and will be broadcast live on Sky Sports F1. Fans can also stream every race without a long‑term contract via NOW, with the option to cancel at any time. As the season progresses, the FIA’s handling of the ADUO windows will be closely scrutinised by teams, media and supporters alike, all of whom share a common interest in preserving a fair and competitive championship while allowing technical development to flourish where it is most needed.