Formula 1's five power unit manufacturers are set to vote on a proposed change to how engine compression ratios are measured, potentially taking effect during the summer break. The 2026 power unit regulations currently specify a compression ratio of 16:1, reduced from 18:1 last year. This measurement has historically been taken at ambient temperature when engines are not running.

The proposed tweak comes amid ongoing discussions about engine performance and fairness across manufacturers. The compression ratio saga has been a point of contention, with teams seeking clarity on how these measurements will be standardized. The vote represents a critical moment for the sport's technical regulations heading into the new power unit era.

With the 2026 season approaching, this decision could have significant implications for engine development strategies. The manufacturers' vote will determine whether the measurement methodology changes before teams finalize their designs for the next generation of power units. The outcome will shape how teams approach engine optimization under the new regulations.