The Mercedes power unit is drawing significant scrutiny as Formula 1 pre-season trials commence in Bahrain. Despite Toto Wolff’s assertion that Red Bull sets the standard, competing teams are actively pursuing revisions to the compression ratio inspection protocols prior to the season’s commencement.
Opposing teams are lobbying the FIA to alter measurement methods because Mercedes adheres to the mandated 16:1 compression ratio during stationary assessments at standard temperatures, yet can attain a greater ratio when the car is in motion. Similar to Williams’ team principal James Vowles, Wolff insists that every Mercedes engine fully complies with regulations, though he now acknowledges that regulatory intervention is not entirely off the table.
“I find myself somewhat more perplexed in recent weeks regarding how this issue suddenly gained prominence, as I had been led to believe that no alterations would occur until this past Friday,” Wolff remarked.
When questioned if, since last Friday, he sensed that an FIA intervention might be approaching, Wolff informed journalists, including Motorsport.com: “Indeed, I came across a piece on an Italian news site indicating impending changes, which made me think we ought to be informed!”
While his concluding comment was delivered with a hint of humor, Wolff’s demeanor in Bahrain conveyed a noticeably graver disposition. The essence of Wolff’s communication diverged from his statements to the press at the Mercedes vehicle unveiling. Previously, the Austrian suggested that rival constructors ought to “organize themselves,” but on this occasion, he conceded that Mercedes would be in a dire situation if the other parties united.
“It involves more than just the teams; you require the consent of the regulatory authority and the commercial rights owner, and should they opt to align their views and objectives, then you face significant trouble.”
Toto Wolff, Mercedes
Photo by: Hector Vivas / Getty Images
“It appears to me that the advocacy efforts by the rival engine constructors have greatly intensified in recent months. By this, I refer to clandestine gatherings and confidential correspondence with the FIA, though, of course, nothing remains truly hidden these days. And these actions have precipitated the current circumstances.”
Any regulatory action necessitates a supermajority within the Power Unit Advisory Committee, signifying the agreement of four out of five engine builders, alongside the FIA and FOM. The responsibility now rests with the FIA, and concerning this, Wolff no longer dismisses any potential outcome.
“As you are aware, this sport is consistently unpredictable, therefore one can never assert certainty about any given situation. Throughout the entire development phase of an engine, you maintain very close communication with the FIA regarding your choices, and this was precisely our approach.”
“And we received every assurance that our actions were in strict compliance with the regulations. It’s not as if we’re discussing an enormous performance advantage, yet it seems all our rivals became somewhat discontent and persistently campaigned the FIA.”
Would Mercedes be permitted to compete in Melbourne if the FIA takes action?
Should the FIA modify the measurement methodologies — perhaps by assessing an engine when hot or by employing onboard sensors during operation — the crucial inquiry becomes whether the quartet of Mercedes-engined teams will be allowed to participate in the Australian Grand Prix.
The official approval deadline for all 2026 power units is the first of March, and considering the extensive development periods necessary for engine alterations, very little time remains for adjustments — particularly concerning core structural elements.
George Russell, Mercedes
Photo by: Mark Sutton / Formula 1 via Getty Images
“Indeed, if it transforms into an official rule, compliance with that rule becomes mandatory. And if one is unable to comply with the regulation, then the FIA must devise a mechanism for adaptation, and that remains ambiguous to us.”
“Naturally, engine development spans a considerable duration, involving significant lead times, and being informed that you cannot run the power unit as designed could substantially impair performance.”
Nonetheless, Wolff dismisses any speculation suggesting Mercedes would pursue legal proceedings under such circumstances.
“The prospect of us taking anyone to court simply doesn’t exist. In Formula 1, from my perspective, it’s more crucial than ever to understand the regulations, yet engineering innovation is consistently valued, and for that reason, we consistently uphold the sport’s administration. Should the sport’s governing body elect to alter the rules, whether it opposes or favors our stance, we are simply obliged to accept it.”
Strategic maneuvering regarding “only a handful of horsepower”
To conclude, Wolff explicitly states that, from his perspective, the compression ratio does not represent a significant factor in performance distinction, and narratives suggesting a 10 to 13 horsepower advantage and multiple tenths of a second per lap are inconsistent with actual facts.
“It amounts to merely a small number of horsepower. In British vernacular, one might refer to it as a ‘couple,’ implying closer to two or three. Hence, the likelihood of it creating any substantial impact during a Grand Prix is almost inconsequential. The greater concern lies with the precedent being established, the complexities of implementing a new regulation, the method of oversight, how adjustments would be made if deemed necessary, and its potential effect on ADUO, the engine equalization framework.”
“Because following six races, anyone who considers themselves part of ADUO and possesses an opportunity to close the gap could promptly begin scrutinizing the compression ratio and evolve their engine in an entirely distinct manner, knowing that after the sixth race, they have the option to modify their power unit. Consequently, the range of unforeseen repercussions is vast and immeasurable.”
