The FIA has published the findings from its second Additional Development and Upgrade Opportunities (ADUO) review period. The governing body determined that the Red Bull-Ford Powertrains internal combustion engine (ICE) is currently the benchmark in Formula 1. This decision means Red Bull will not receive any opportunities to upgrade its engine before the conclusion of the 2026 season.
The ADUO system, introduced under Article C4 of the 2026 Technical Regulations, aims to prevent any single power unit manufacturer from maintaining a prolonged performance advantage. It focuses specifically on the ICE, creating an ‘ICE Performance Index’ based on factors such as engine speed, input shaft torque, MGU-K power, and lap-time sensitivity.
Manufacturers whose ICE performance falls at least 2% behind the benchmark during defined review periods are granted additional homologated upgrades. These concessions also include increased cost cap allowances and extra dyno testing hours.
For the first ADUO period, which concluded after the Canadian Grand Prix, Mercedes was found to be in the 2-4% deficit window. This allows the German manufacturer one additional homologation in 2026 and another in 2027.
Ferrari, Audi, and Honda were determined to be more than 4% behind the leading ICE. Consequently, these three manufacturers are permitted two additional homologations for both the 2026 and 2027 seasons.
The FIA confirmed that no additional homologations were granted to any power unit manufacturers following the second review period, which concluded after the Hungarian Grand Prix. This suggests a tightening of engine output margins during the early summer.
Red Bull had previously expressed surprise at the initial findings after the Monaco Grand Prix, where their engine was first identified as the benchmark. Team Principal Laurent Mekies requested a factual review of the results.
‘We certainly would like to have extreme certainty in the way you are assessing the ICE pecking order,’ Mekies stated, ‘especially when you get relative performance variations from track layout to track layout that are perfectly consistent with the ICE power sensitivity.’
Mekies also highlighted a potential ‘risk’ for Red Bull, as the team cannot upgrade its ICE while rivals gain opportunities to develop other power unit components. Red Bull-Ford Powertrains is in its inaugural year of developing its own Formula 1 engine.
Nikolas Tombazis, FIA Director of Single-Seaters, defended the accuracy of the governing body’s measurements. He stated that the analysis undertaken was ‘thorough and exhaustive,’ providing a high level of confidence in the findings.
However, Tombazis acknowledged that the ADUO system has ‘weaknesses’ and requires refinement for future seasons. He indicated that the FIA aims to make the process less time-consuming and controversial.
The FIA maintains confidentiality regarding specific power unit performance index measurements. A third ADUO review period for the 2026 season is scheduled to take place after the Mexico City Grand Prix.
