Formula 1 manufacturers made progress with the FIA on Thursday in agreeing a way for compression ratios to be measured when engines are running hot, but this new procedure remains unlikely to be implemented in the short term.
The FIA called a gathering of engine technical experts from each of the competitors to discuss the row that has erupted over a potential exploitation of F1's compression ratio rules.
Rivals of the Mercedes- and Red Bull-powered teams have suspicions that the two engine makers have found a way to run their engines at a higher compression ratio than the rules theoretically allow.
This is being done because F1's technical regulations stipulate that the 16:1 limit that has come into force for 2026 is only measured at ambient temperature.
The suggestion is that Mercedes and to a lesser extent Red Bull are using clever designs that increase the compression ratio when the engine is running hot - delivering a performance boost.
With Ferrari, Audi and Honda having written to the FIA seeking some answers concerning legality, the governing body arranged a meeting with technical experts on Thursday to try to agree a roadmap for the future.
Sources suggest that the meeting was productive in terms of there being alignment about how the measurement of compressions ratios can be taken in the future when engines are running at hot temperatures.
Such an agreement on the methodology of a new measurement system, however, does not mean that it will be fast-tracked and brought in immediately.
The next step will be to engage in discussions with manufacturer bosses about whether there are grounds to propose F1's technical rules change to adopt the new procedures for measurements when hot.
Whether this is pushed for this season or is aimed at 2027, such a regulation tweak would need to go through the proper governance channels: a formal vote in the F1 Commission.
And as there are four Mercedes-powered teams and two Red Bull squads, the two manufacturers hold majority sway - which means any alterations to the rules will not be easy to achieve without their backing.
Even Mercedes' rivals were not anticipating anything changing in the short term from the meeting though.
Audi's F1 project chief Mattia Binotto said his expectation from Thursday's gathering was just to get a method of measurements agreed.
"My hope in that meeting is not clarity on the regulation itself, but more to define a methodology for the future," he said at Audi's season launch in Berlin earlier this week.
For now, the rules as they are written stand - so measurements are taken at ambient temperature.
It means that any advantage Mercedes and Red Bull have managed to get will remain in place for the time being.
