Story byMotorsport photoRoberto ChincheroSat, December 20, 2025 at 11:45 AM UTC·2 min readFormula 1’s new 2026 power units will debut at the Circuit de Catalunya in just over five weeks’ time, but questions over a grey area of the new regulations have already come to light. German outlet Motorsport Magazin revealed that some engine manufacturers have sent a request for clarification to the FIA regarding the compression ratio, one of the parameters changed in the 2026 regulations. This represents a reduction from the 18.0:1 value set by the previous regulations, now lowered to 16.0:1 for the upcoming season. AdvertisementAdvertisementAdvertisementMercedes, and potentially Red Bull Powertrains, are said to have found a way to circumvent what is stipulated in the technical regulations, according to which the compression ratio must comply with the specified value during checks carried out at ambient temperature. Suspicions that it might be possible to change the compression ratio as temperatures vary have led Ferrari, Audi and Honda to request FIA involvement. Attention has focused on the use of materials that could expand as operating temperatures rise, helping to increase the compression ratio. This would be a violation of the technical regulations, which reiterates that the cars must be compliant at all times during a race weekend. AdvertisementAdvertisementAdvertisement2026 FIA F1 car render2026 FIA F1 car renderThe FIA has said: “The topic has been and continues to be discussed in the technical forums with the PUMs (power unit manufacturers), as the new limit naturally raises questions about interpretation and compliance.
