FIA to review ADUO after Red Bull engine ranking surprise

FIA takes second look at ADUO outcome

The FIA has agreed to review its findings from the Additional Development and Upgrade Opportunities programme after Red Bull Powertrains was assessed as having the best-performing engine in Formula 1.

The matter came into focus after the Monaco Grand Prix, when Lewis Hamilton revealed that Mercedes HPP, Ferrari, Audi and Honda were all set to receive assistance through the ADUO mechanism. That disclosure followed Red Bull Powertrains being judged to have the strongest engine under the FIA’s assessment.

Why the Red Bull ranking raised eyebrows

The result prompted surprise because ADUO is measured only against performance metrics for the internal combustion engine, rather than the complete power unit. That distinction is central to the controversy surrounding the initial findings.

Red Bull Powertrains being classified at the top of the engine performance table sits against a backdrop of stated reliability concerns, while Mercedes HPP-powered cars have won all six grands prix and three sprints so far. However, under the ADUO methodology as described, the wider competitive picture does not define the measurement.

Mercedes HPP has been found to be within two per cent of Red Bull Powertrains. As a result, it earns one ADUO upgrade for 2026 and another for 2027, alongside additional budget cap allowance.

Audi, Ferrari and Honda are understood to be more than four per cent behind, making them eligible to receive two tokens per year under the programme.

FIA yet to publish formal communication

The FIA has not formally released its ADUO findings at the time of writing. The metrics used to gather the data have also not been made public, either to teams or externally.

That secrecy is deliberate. The aim is to prevent power unit manufacturers from effectively gaming the system by appearing slower than they really are in order to obtain upgrade tokens they would not be entitled to on pure performance grounds.

Hamilton’s post-Monaco comments therefore landed before the governing body had issued its official position. With the FIA now reviewing the findings, the final ADUO picture remains subject to formal confirmation.