Wolff claims FIA chief backs Mercedes in compression‑ratio dispute

Mercedes team principal Toto Wolff says FIA president Mohammed Ben Sulayem has consistently backed Mercedes in the compression‑ratio dispute. An e‑vote on a proposed hot‑temperature test is scheduled for 28 February, and Mercedes will accept the outcome.

Why it matters:

• The test could set a precedent for how temperature‑dependent engine rules are enforced, impacting future technical battles.
• A required redesign would affect all power‑unit makers, shifting cost and performance dynamics across the grid.

The details:

• Mercedes and Red Bull were accused of using a loophole that lets higher compression at hot engine temps, since measurements are taken only at ambient temperature.
• Rival manufacturers (Ferrari, Audi, Honda, Red Bull Powertrains) have proposed a hot‑temperature test to the Power Unit Advisory Committee (PUAC), which put the proposal to an e‑vote.
• The e‑vote, due 28 February, requires a super‑majority that includes the four manufacturers, FIA president Mohammed Ben Sulayem and commercial rights holder Stefano Domenicali to pass.

What's next:

• If approved, the test would be enforced from 1 August 2026, ahead of the new power‑unit era.
• Mercedes said it will respect the outcome, and the decision will shape how 2026 engine regulations are applied.