Blow for Red Bull as FIA reveals results of second F1 ADUO engine review
F1's governing body the FIA has published its findings after the second ADUO period.
Red Bull will not permitted an opportunity to upgrade its first-ever Formula 1 engine before the end of the 2026 season.
Governing body the FIA has announced the findings of its second round of analysis into the performance of F1’s power unit manufacturers and whether they will provided Additional Development and Upgrade Opportunities (ADUO).
In a shocking turn of events after the Monaco Grand Prix, it emerged that Red Bull had been deemed as having F1’s best engine.
It was widely believed in the paddock that Mercedes has the best performing power unit following a dominant start to the 2026 season, but the FIA’s findings suggested otherwise.
Red Bull requested a factual review of the results, with team principal Laurent Mekies adamant that there was “not a single data point” suggesting that Red Bull-Ford Powertrains was leading the way.
A public announcement had been expected in the weeks after Monaco but never came.
However, on Wednesday, the FIA published its findings for both the first and second periods of its evaluations. The first concluded after the Canadian Grand Prix and the second concluded after the Hungarian Grand Prix.
The FIA’s results officially confirm that Red Bull was deemed to have the strongest engine, with Mercedes determined to be in the 2-4% window, enabling the German manufacturer one upgrade in 2026 and two homologations in 2027, alongside cost cap and dyno testing increases.
Ferrari, Audi and Honda were all found to be above the 4% threshold, enabling all three manufacturers two upgrades for both 2026 and 2027.
The FIA confirmed that “no additional homologations were granted to any of the Power Unit Manufacturers” for the second period.
A statement added that “due to the confidential nature of this information, no further details on Power Unit performance index measurements will be communicated.”
Nikolas Tombazis, the FIA director of single-seaters, expressed confidence in the governing body’s findings.
“The FIA has undertaken thorough and exhaustive analysis as part of our ADUO review process,” Tombazis said.
“With the release of the findings of period 2, we are confident that, based on the quality of the data, its analysis is incredibly robust, giving us a high level of confidence in our findings.
"We also have to respect the confidentiality and intellectual property of the teams and their Power Unit Manufacturers in disseminating any details from the findings.
“This is the first year of ADUO so naturally there are areas which we may evolve over time, in discussion with all the PU Manufacturers”
A third ADUO review period for the 2026 season will take place after the Mexico City Grand Prix.
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