Mercedes handed F1 2026 blow as FIA power unit talks take fresh twist

Toto Wolff, Kimi Antonelli, George Russell, Mercedes, Bahrain, 2026 — Photo: © IMAGO

Latest F1 News

Mercedes handed F1 2026 blow as FIA power unit talks take fresh twist

A twist in the compression ratio row

Sheona Mountford F1 Journalist

Motorsport journalist working in F1 since 2024.

Thursday 26 February 2026 20:52

A new twist has emerged in the Mercedes F1 compression ratio saga just under a week away from lights out in Melbourne.

If you've had your fingers in your ears and been singing 'la-la-la' the past few months, you may have missed the row rumbling over Mercedes 2026 power unit.

It appears the boffs at Brixworth discovered a loophole in the regulations, allowing Mercedes to run their car at the legal 16:1 ratio during the static tests, but that ratio then rises closer to the previous limit of 18:1 when running. At higher temperatures however, there is currently no way to measure the compression ratio.

Article continues under video

Naturally, the other power unit manufacturers weren't best pleased, especially as the trick could bestow a 0.3 second advantage upon Mercedes.

ALBERT PARK: Your essential guide to the Australian Grand Prix track

F1 power unit tests could be brought forward

After a meeting of the F1 Commission in Bahrain, the FIA revealed a proposal to measure the ratios at both high temperatures and ambient temperatures, with power unit manufacturers due to vote on the role. A supermajority of six out of seven votes is required.

If they do vote in favour of measuring at higher temperatures, this wouldn't come into effect until August 1 by which time half of the F1 season will have been contested.

Now, according to Motorsport-Magazin.com, a fresh twist could see further compromise and this date amended. The deadline could instead be brought forward to June 1 and the week before the Austrian Grand Prix.

Furthermore, although measurements will be taken in cold and hot conditions for the rest of the 2026 season, but from 2027 measurements will only be taken in hot conditions.

F1 Engine Compression Ratio: What is it and why is it so controversial?

F1 Mercedes FIA 2026 regulations