FIA makes latest ADUO ruling and hints at 2027 revamp
The FIA's third round of analysis of Formula 1 engine performance has been concluded, with no change to the pecking order under its Additional Development and Upgrade Opportunities (ADUO) system.
It means Red Bull remains the only manufacturer unable to upgrade its F1 engine under the catch-up system.
The ADUO mechanism, which ranks the power unit manufacturers on internal combustion engine performance alone, is new for 2026 but its introduction has not been without controversy and it could be tweaked for 2027 to work better at both ends of the competitive order.
The FIA announced on Tuesday following the Brazilian Grand Prix weekend that it had gathered the results of its third analysis period - covering rounds 12-18, so the Dutch GP in August to the US GP in October - and that these had been communicated to manufacturers.
It said that although gaps to the leading internal combustion engine - Red Bull - had "evolved", that "did not result in any additional homologations being granted to the power unit manufacturers".
Mercedes was therefore determined to be in the 2-4% window behind Red Bull, and has one additional homologation for 2026 (still yet to be introduced) and another for 2027.
Audi, Ferrari and Honda are granted two additional upgrades for 2027 as they are still deemed to be more than 4% off Red Bull. Both Ferrari and Honda have deployed both of their permitted 2026 upgrades already, but Audi is understood to be saving its next upgrade for the 2027 season.
Along with that ADUO allowance are cost cap and dyno testing increases for all four manufacturers.
As per the previous round of official results, the FIA said "no further details on power unit performance index measurements will be communicated".
Mercedes was determined to be in the 2-4% window, and is thus allowed one additional homologation in 2026 and an additional one in 2027, together with corresponding cost cap and dyno testing increases.
Audi, Ferrari and Honda were determined to be above 4%, and are thus allowed two additional homologations in 2026 and 2 in 2027, together with corresponding cost cap and dyno testing increases.
"Based on the quality of the data and the robustness of the assessment process, we are confident in our findings and the conclusions reached," said FIA single-seater director Nikolas Tombazis.
He added that with the first year of ADUO's use essentially complete - there will be no additional rounds of analysis of 2026 - that it had "reinforced our belief" that it was the correct concept, but, as reported by The Race in September, he suggested that changes will be made to the system for 2027, when new fuel-flow rates also come into play.
"We have been working closely with the Power Unit Manufacturers and teams to explore refinements to the methodology that will support the continued effectiveness of ADUO in future seasons," said Tombazis.
Options previously being considered were changes to the way internal combustion engine power is measured to account for turbo size, operating temperatures, and outside factors such as exhaust wings.
Another route was to base the rankings on overall power unit performance rather than just the internal combustion engine element.
Audi project chief Mattia Binotto also suggested earlier in the year that it would be better to base allowances for improvement on constructors' championship positions and not a judgement on the power of a single component.
