Mercedes manager Toto Wolff said he was “philosophically” opposed to the FIA’s proposal for a mid-season rule change over the controversial engine element, but his team was trying to be “good citizens” by accepting it despite the potential negative impact on performance.
A dispute over compression ratio limits for F1’s new power units for 2026 has seen Mercedes’ rival engine manufacturers lobbying the sport’s governing body to prevent the Silver Arrows from exploiting loopholes in the rules.
The FIA announced on Wednesday that it had submitted a proposal to formally close the loophole during the sport’s summer break in August, with a vote expected to take place before the season-opening Australian Grand Prix on March 8.
For the rule change to pass, all four other engine manufacturers – Ferrari, Red Bull, Honda and Audi – will need to vote in favor of the change, along with the FIA and F1.
Wolff made the announcement on Thursday, the penultimate day of pre-season testing in Bahrain, and reiterated his position that Mercedes’ rivals were exaggerating the importance of the issue, but softened his previous stance of aggressively resisting potential rule changes.
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Craig Slater described the latest FIA meeting where a solution to Mercedes’ engine problems was found, although the team was unable to gain an advantage in terms of compression ratio.
“I’ve always said this is a storm in a teacup, and then these numbers come out…If these numbers are true, I understand why someone would fight, but ultimately it’s not worth fighting for,” Wolff said.
“Whether we stay like this or change to new regulations, nothing changes for us. It’s a process.
“But we also want to be good citizens of the sport, because it doesn’t make a huge difference that we changed our minds.
“Philosophically, I believe that regulations should be made and we should keep the FIA close to us, so you can and should be against it.”
“But if there are four other PU (manufacturers) that are putting so much pressure on the FIA, at some stage what choice do we have but not to play?
“We were pretty comfortable that there would even be protests in Melbourne on Friday, but is this what we want?”
The compression ratio limit has been lowered from 18.0 in the previous ruleset to 16.0, but measurements are now only taken when the engine is not running at maximum temperature, and Mercedes’ rivals have suggested they are exploiting this by exceeding the limit when the engine is hot.
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Toto Wolff has slammed rival F1 teams by criticizing the legality of Mercedes’ new engine.
Asked whether the rule change could have a negative impact on the performance of Mercedes’ power unit, Wolff replied: “I don’t think anyone would benefit from the current approach (based on the proposed changes), where you have to follow the rules both when it’s cold and when it’s hot.”
“I think the other players were trying to get us to only measure the hot stuff so they could actually go cold outside of regulation. So now it’s fair game for everyone.”
Wolff outraged over suggestion of ‘illegal fuel’
Wolff also expressed frustration at reports this week that Mercedes’ fuel supplier Petronas was facing a race against time to get fuel approved for the season opener in Melbourne.
Motorsport.com reported earlier this week that Petronas will also supply fuel to three other teams that use Mercedes power units – McLaren, Williams and Alpine – but have not yet received certification and homologation for their products.
New sustainable fuels to be introduced in 2026 are subject to strict checks, and the report claims Mercedes and its customer teams will be forced to use “interim” fuels if Petronas products are rejected.
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Check out the highlights from the morning session of Day 2 of the 2nd Bahrain Pre-season Test.
When asked about the report, Wolff said: “That’s another story. We were told the compression ratio was illegal, but it’s bullshit, it’s bullshit.”
“And now the next story comes out that our fuel is illegal. I don’t know where it came from, but it starts spinning again.
“Maybe tomorrow we’ll invent something else…God knows what will happen, right?
“It’s also nonsense. This (fuel) is a complex subject, processes and all that, but it’s not really… I can’t even comment on it.”
Sky Sports F1 Bahrain test schedule
Friday, February 20th
Watch every race of the 2026 F1 season live on Sky Sports, including the Australian Grand Prix from March 6-8. Stream Sky Sports now – cancel anytime with no contract
6:50am to 11:05am: Morning session live 11:55am to 4:10pm: Afternoon session live 8pm: Test lap
