ADUO engine‑rule fight

Formula 1’s 2026 engine fight is no longer just about who built the fastest power unit in winter testing. It is now about whether the FIA will hand struggling manufacturers extra upgrade room through a rule called Additional Development Upgrade Opportunities, or ADUO. (crash.net) A modern F1 power unit is a hybrid system: a 1.6-litre turbo V6 paired with electrical recovery hardware and a battery. Under the 2026 rules, electric output rises to 350 kilowatts, up from 120kW in the current era, while the internal-combustion side drops to about 400kW and the cars run on 100% sustainable fuel. (formula1.com) Those engines are largely homologated, which means manufacturers cannot freely redesign them once the season starts. ADUO was added as a catch-up mechanism so a supplier judged to be behind can make limited changes instead of being locked into a bad package for years. (crash.net) Crash reports the FIA set three review windows during the season, and manufacturers measured at between 2% and 4% behind the class-leading engine can get one immediate change. If the deficit is more than 4%, they can also receive extra dyno time and more flexibility under the power-unit cost cap. (crash.net) That matters in 2026 because the new engine formula was written to attract more brands, not fewer. The FIA approved the rules in August 2022 with goals that included limiting performance gaps, using up to 50% electrical power and making the championship attractive to new power-unit manufacturers. (fia.com) The political risk is obvious: every manufacturer wants the FIA to judge its engine fairly, but nobody wants a rival to get a free in-season leap. Sky Sports says Miami’s Sprint weekend on May 1-3 is the first real pressure point, because ADUO decisions could shape the competitive order early in the new rules cycle. (skysports.com) Miami is also where other 2026 rule tweaks are due to begin. Formula 1 said on April 20 that changes agreed by the FIA, teams, power-unit bosses and Formula One Management after Australia, China and Japan will start from the Miami Grand Prix weekend, including new energy-management limits and race-start safety measures. (formula1.com) Those changes were aimed at two early problems: excessive energy harvesting and dangerous speed differences when some cars accelerated poorly. Formula 1 said maximum permitted recharge will fall from 8 megajoules to 7MJ, peak “superclip” power rises from 250kW to 350kW, and a low-power start-detection system will trigger automatic MGU-K deployment if a car launches abnormally slowly. (formula1.com) Paddock criticism is not only about safety. Crash quoted Anthony Davidson warning F1 could go down “a dangerous path” if ADUO is handled badly, while rival teams have raised fears that opaque measurements or strategic underperformance could turn an engineering rule into a lobbying contest. (crash.net, skysports.com) Audi, one of the manufacturers most often linked with ADUO, has already signaled that any recovery will take time. Mattia Binotto said at Suzuka that “miracles are not possible” because engine development lead times are long, even with a regulatory catch-up system in place. (crash.net) So the first big 2026 engine question is no longer who guessed right last year. It is whether the FIA can prove, starting in Miami on May 1-3, that ADUO is a transparent repair tool and not a second championship fought in meeting rooms. (formula1.com, skysports.com)