Formula 1 was rocked by a new technical controversy just before the iconic Monaco Grand Prix. McLaren, one of the championship’s historic teams, was accused of using an engine with “super composite” components that were not declared or approved by the FIA. According to sources close to the paddock, the scandal reached such proportions that the Fédération Internationale de l’Automobile (FIA) immediately intervened, ordering the complete sealing of the MCL39 car for a thorough technical inspection.
It all started after the MCL39’s unexpected performance in the last two races, particularly at Imola, where Lando Norris and Oscar Piastri both showed surprisingly high pace on the high-downforce stages. Some rival teams, including Mercedes and Aston Martin, reportedly raised suspicions after comparing telemetry data and recording unusual acceleration out of slow corners, a characteristic that would indicate an alteration in the engine’s power delivery.
The controversy intensified when rumors emerged that McLaren had introduced an experimental component into the combustion chamber of the supplied Mercedes engine, developed in collaboration with a third-party composite supplier in Switzerland. This component, classified as a “carbon-ceramic hybrid supercomposite,” is said to be designed to withstand higher temperatures and improve the engine’s thermal efficiency, generating an increase in power during peak acceleration.
Alerted by these allegations, the FIA acted quickly. During the technical inspection following the Emilia Romagna GP, the #4 MCL39 (Norris’s car) had to be sealed to prevent any modifications before its technical analysis in Paris. A source close to the McLaren team confirmed that the car has already been transported in a sealed container and is in the custody of FIA officials. The analysis will focus not only on the integrity of the engine, but also on the legality of any structural modifications to the chassis that may have benefited the engine’s thermal performance.
McLaren, for its part, denies any violation of the regulations. In a brief statement, the Woking-based team stated that “all developments regarding the MCL39 have been transparently communicated to the FIA, including every technical update made since the start of the 2025 season.” However, they did not provide any specific details on the alleged “supercompound,” which intensified the hype.
In the paddock, the reaction was immediate. Mercedes boss Toto Wolff was cautious but firm: “It is essential that the technical regulations are respected. If it is proven that someone has exceeded their limits, there must be consequences.” Red Bull’s Christian Horner, meanwhile, was more ironic: “Perhaps McLaren has discovered the secret of the nuclear engine…”
The timing couldn’t be more tense. The Monaco GP is traditionally a key showcase for sponsors and manufacturers, and any technical dispute at this stage of the season has implications beyond sporting performance. If the FIA discovers irregularities, McLaren could be disqualified from previous races, fined millions of dollars, or even temporarily suspended from racing.
Meanwhile, fans and analysts are divided. Some see the accusation as a pressure tactic by rivals annoyed by McLaren’s sudden rise in the standings. Others, however, believe it could be the biggest technical scandal since Renault’s mass dampers in 2006.
With the investigation underway and the MCL39 under scrutiny, the atmosphere in Monaco is more tense than ever. What was supposed to be a weekend of glamour and precision on the streets of the Principality could become the epicenter of a regulatory earthquake that will shake the foundations of the 2025 championship.
