Toto Wolff, Mercedes Team Principal, stated that Mercedes possesses the most powerful power unit on the Formula 1 grid. This declaration followed Kimi Antonelli’s victory at the Belgian Grand Prix on Sunday, July 19, 2026. Wolff’s comments contradict the FIA’s recent assessment, which ranked Red Bull’s internal combustion engine as the benchmark.
The FIA’s Additional Development and Upgrade Opportunities (ADUO) system, introduced for the 2026 to 2030 power unit regulations, aims to balance engine performance. In June 2026, the FIA determined Red Bull Powertrains held the strongest internal combustion engine (ICE). This meant Red Bull received no development tokens.
Conversely, Mercedes was rated more than two percent behind Red Bull’s ICE benchmark. This deficit granted the Brackley squad one homologation token for the current 2026 season and another for 2027. Ferrari and Audi were assessed with even larger performance gaps, receiving additional tokens.
The current debate follows an earlier controversy from February 2026 concerning Mercedes’ 2026 power unit. Rivals suspected Mercedes had exploited a loophole in the new compression ratio regulations. The rules set a 16:1 compression ratio limit, but Mercedes was believed to achieve a higher ratio at operating temperature.
At the time, Wolff admitted Mercedes would be ‘screwed’ if the FIA altered the rules before the season commenced. He expressed confusion regarding the sudden emergence of the issue, indicating prior assurances that regulations would remain unchanged. Wolff also cited extensive lobbying efforts by other engine manufacturers.
In response to these concerns, the FIA implemented new compression ratio testing procedures from June 1, 2026. These revised checks now include measurements at operating temperatures, effectively addressing the alleged loophole. This regulatory adjustment aimed to ensure fair competition.
Wolff’s recent assertion about Mercedes’ power unit strength suggests a comprehensive advantage beyond the ICE component alone, which is what the ADUO system primarily measures. McLaren driver Lando Norris also observed that Mercedes-powered cars appeared to have ‘turned their power units up’ at the Belgian Grand Prix.
The Belgian Grand Prix saw Kimi Antonelli secure his sixth victory of the 2026 season, extending his lead in the Drivers’ Championship. The 19-year-old Italian started from pole position at Spa-Francorchamps and navigated an eventful race to claim the win.
Antonelli’s triumph further solidifies his impressive 2026 campaign, which includes earlier wins in China, Japan, and Miami. He currently leads the Drivers’ standings, having become the youngest driver in history to achieve three consecutive F1 wins and to lead the World Championship.
During the Belgian Grand Prix, Antonelli’s teammate George Russell retired after a collision with Ferrari’s Lewis Hamilton on the opening lap. Charles Leclerc finished second for Ferrari, with Max Verstappen securing third place for Red Bull.
