Toto Wolff warns Mercedes could be 'screwed' in crucial F1 engine vote

Mercedes Team Principal Toto Wolff has publicly stated his team could be "screwed" if a crucial vote passes to change how engine compression ratios are measured, a move targeting an alleged performance trick used by Mercedes' power unit division. The vote, requiring a supermajority, hinges on the FIA and FOM's decisions, with Red Bull Powertrains having switched sides to support the new test.

Why it matters:

This vote represents a high-stakes regulatory and political battle that could invalidate a key performance differentiator for Mercedes' 2026 power unit before the season even begins. The outcome will set a precedent for how technical loopholes are addressed and could significantly alter the competitive balance for the new engine formula, impacting not just Mercedes but all its customer teams.

The details:

• The controversy centers on the technical regulation requiring a maximum compression ratio of 16:1. The current rules measure this at ambient temperatures, but Mercedes HPP is alleged to have designed its engine to operate at a higher, more powerful ratio when hot on track, using heat-expanding metals.
• The proposed change would mandate measuring the compression ratio while the engine is hot, effectively closing this potential loophole.
• The Power Unit Advisory Committee (PUAC) vote requires a supermajority: four of the five power unit manufacturers (Mercedes, Red Bull, Ferrari, Honda, Audi), plus the FIA (regulator) and FOM (commercial rights holder).
• Red Bull Powertrains has reportedly joined Ferrari, Honda, and Audi in supporting the new test, leaving Mercedes isolated. The deciding votes now belong to the FIA and FOM, who have not declared their stance.
• Wolff revealed that FIA President Mohammed Ben Sulayem had previously supported Mercedes' interpretation of the rules, stating "it was clear what the regulation said." Wolff now questions if the governing bodies will share "an opinion and an agenda."
• If the vote passes and Mercedes' design is deemed non-compliant, the engines would need to be re-homologated by the March 1st deadline, a costly and time-critical challenge.

What's next:

The impending vote puts immense pressure on the FIA and FOM to make a ruling that will be seen as either upholding the technical intent of the rules or bowing to competitive pressure from rival manufacturers.

• A vote in favor of the change would force Mercedes HPP into a frantic redesign to meet the homologation deadline, potentially costing performance and reliability.
• A vote against the change would likely trigger protests and accusations of favoritism, especially given Wolff's disclosure of prior support from the FIA president.
• The result will immediately define the pecking order expectations for the 2026 season and shape the political landscape between the power unit suppliers for years to come.