FIA announce ADUO ruling as Mercedes and Ferrari handed boosts

The FIA has revealed its results from the first two official reviews of the ADUO (Additional Development and Upgrade Opportunities) system.

Red Bull has been deemed to possess the best engine in the field, meaning its rivals will receive extra chances to catch up.

The system was introduced this year at the start of a fresh regulation cycle, with an even split created between the combustion engine and battery.

The FIA has not outlined what the metrics are to come to such a ruling, but the Red Bull Powertrains build has been declared the most efficient engine, despite it being its first year as a power unit manufacturer.

Mercedes, as a result, will have an extra opening to introduce one upgrade for 2026 and another for 2027 due to being more than two per cent adrift of the benchmark.

Ferrari, Audi and Honda, meanwhile, will be allowed two upgrades for 2026 and two for 2027 - the maximum allowable - as they have been deemed more than four per cent down.

Mercedes will get an extra $3 million cost cap allowance and an extra 70 hours of bench testing due to their deficit.

A sliding scale then follows - 4-6 per cent away gets $4.65m and 100 bench hours, 6-8 per cent off gets $6.35m and 150 hours, and those who are 8-10 per cent off are awarded $8m and 190 hours.

The FIA has not detailed where exactly on the scale Ferrari, Audi and Honda sit.

The final ADUO period this year will cover rounds 12–18, from the Netherlands to Mexico City.