The FIA is currently reviewing its engine performance findings after Red Bull was identified as having the top Formula 1 engine according to the Additional Development and Upgrade Opportunities (ADUO) system. This evaluation covered the 2026 power unit manufacturers, including Mercedes, Ferrari, Audi, and Honda.

A document obtained by Sky Sports News indicates that only Red Bull will not receive engine upgrades this season, as they are considered the benchmark. Other teams will receive the following upgrades based on their performance:

• Mercedes: One upgrade (over 2% behind Red Bull)
• Ferrari, Audi, Honda: Two upgrades each (over 4% behind Red Bull)

Despite their top ranking, Max Verstappen expressed surprise at the results, especially considering Mercedes has won six out of seven races this season. Red Bull team principal Laurent Mekies emphasized the need for further dialogue with the FIA to clarify their ranking, stating, "We do not see one single data sample that indicates that we would have an advantage over our friends at Mercedes."

The ADUO system focuses solely on internal combustion engine performance and does not account for the electrical components, which contribute significantly to overall power output. Toto Wolff, Mercedes team principal, defended the FIA's findings, arguing that the data is unbiased and reflects accurate measurements.

Critics like Martin Brundle and Jacques Villeneuve question the fairness of the ADUO system, suggesting it undermines the spirit of competition in F1. Brundle remarked, "Formula 1 is about excellence, not the lowest common denominator," while Villeneuve expressed concerns about the implications of allowing one team to improve while restricting another.

The FIA plans to conduct two more ADUO reviews this year, which will influence the 2027 season after the Hungarian Grand Prix and the Mexico City Grand Prix.