Mercedes engine row forces FIA rule shake-up before F1 season begins
Formula 1’s governing body has confirmed that a new technical test will be introduced during the 2026 season following concerns from several teams about how engine compression ratios could be measured under the sport’s new rules.
According to Sky Sports journalist Nigel Chiu, the debate emerged during the winter as teams examined the regulations that will govern the sport’s new generation of hybrid power units.
The FIA said the rule clarification comes after feedback from teams and drivers during pre-season testing in Barcelona and Bahrain.
Engine dispute over compression ratio
Under the 2026 regulations, the permitted compression ratio for engines has been reduced from 18:1 to 16:1 as part of the sport’s broader technical overhaul.
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However, the initial regulations specified that measurements would only be taken when engines were not at full operating temperature.
According to Sky Sports, some teams believed this left room for a potential workaround at higher temperatures. Mercedes was widely linked to the discussion, although no team was formally accused of breaking the rules.
To address the issue, the FIA confirmed that from June 1 the compression ratio will be tested both in cold conditions and at operating temperature, which is defined as 130°C.
The governing body also stated that any system designed to allow an engine to exceed the 16:1 ratio during operating conditions will be prohibited.
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Formula 1’s current power-unit manufacturers include Mercedes, Ferrari, Red Bull Ford, Audi and Honda.
Mercedes and rivals respond to the debate
Mercedes team principal Toto Wolff initially warned that altering the regulations could negatively affect performance development.
Later, however, he played down the significance of the issue.
“We said it all along that this looks like a storm in a teacup,” Wolff said.
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“It doesn't change anything for us, whether we stay like this or whether we change to the new regulations.”
According to reporting by Sky Sports, the debate appeared to divide engine manufacturers. Ferrari, Audi and Honda were said to favour clarification of the rules, while Red Bull previously described the controversy as exaggerated.
FIA single-seater director Nikolas Tombazis also suggested the situation had received more attention than necessary.
“I don't think this topic ever needed to get to the level of attention that it has,” Tombazis told Sky Sports.
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Additional regulation adjustments for 2026
Alongside the engine clarification, the FIA confirmed several smaller sporting regulation updates for the 2026 season.
Qualifying’s final session, Q3, will be extended from 12 minutes to 13 minutes. To keep the overall qualifying session within one hour, the break between Q2 and Q3 will be shortened from eight minutes to seven.
The governing body also confirmed that the experimental rule requiring two mandatory pit stops at the Monaco Grand Prix last season will not return. The race will instead follow the same regulations used at other events.
The 2026 Formula 1 season begins with the Australian Grand Prix in Melbourne, marking the first campaign under the sport’s sweeping new technical rules.
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Sources: Sky Sports
