F1 Today | Mercedes engine edge under threat amid major leadership overhaul at Pirelli

The FIA’s meeting with power unit manufacturers in Bahrain, held to tackle the ongoing compression-ratio controversy, has led to fresh discussions and a revised direction on the matter.

An initial proposal suggested that, from 1 August 2026, compliance checks on the compression ratio would no longer be carried out solely under ambient conditions, but also at a representative operating temperature of 130°C. However, that version of the plan now appears to have lost momentum.

Teams pushing to limit Mercedes’ perceived advantage are reportedly dissatisfied with the proposal as it stands, having favoured testing exclusively under hot operating conditions. Measuring both cold and hot scenarios could potentially disadvantage them as well, prompting further negotiations.

As a result, a new compromise is being considered, including bringing the introduction date forward to 1 June and implementing a two-phase approach currently under discussion.

Pirelli have confirmed that Mario Isola will step down from his role as head of motorsport ahead of the 2026 Formula 1 campaign, marking the end of a long-standing chapter within the company’s racing division.

In an official announcement, the Italian tyre manufacturer revealed that Dario Marrafuschi will take over the position from March 1, assuming responsibility for all motorsport programmes, including Formula 1 tyre operations. Isola has overseen Pirelli’s F1 activities since the brand returned as the sport’s sole tyre supplier in 2011.

To guarantee continuity during the handover, Isola will remain with the company until July 1 before departing to explore new professional opportunities.