According to the FIA's recent analysis following the 2026 Monaco Grand Prix, Red Bull has the top-performing engine in Formula 1, as determined by its Additional Development and Upgrade Opportunities (ADUO) program. This program evaluates various performance metrics of internal combustion engines (ICEs) over three review periods during the season. The first review included five races: Australia, China, Japan, Miami, and Canada. Teams that fall at least 2% behind the leading engine are eligible for upgrades, allowing them to continue developing their engines while Red Bull's engine remains frozen. Mercedes, which dominated the early season, is now recognized as being over 2% behind Red Bull, thus qualifying for additional spending on upgrades. Meanwhile, Ferrari, Honda, and Audi are more than 4% behind, enabling them to receive multiple upgrades this season and next. However, implementing these upgrades will take time, with Lewis Hamilton noting that it could be an eight to ten-month project. The ADUO initiative aims to promote closer competition in the wake of recent F1 technical regulations requiring a balanced split between electrical and ICE power.