Tombazis on Mercedes compression ratio: “The FIA has never said it was illegal”
The FIA’s Single-Seater Technical Director has clarified the process that led to the upcoming online vote of the Power Unit Advisory Committee (PUAC) regarding the Mercedes compression ratio debate.
Awaiting the online vote
As reported in recent days, the issue concerning the compression ratio of the Mercedes power unit — which is believed to be capable of varying beyond the regulatory 16:1 limit — will be decided through an online vote of the PUAC. The proposal on the table introduces a new measurement system, no longer conducted at ambient temperature but at 130°C, starting from August, that is after 13 Grands Prix of the 2026 Formula 1 World Championship.
To obtain final approval, pending ratification by the World Motor Sport Council, six votes out of seven will be required. In addition to the four rival power unit manufacturers — Audi, Ferrari, Honda and Red Bull — the proposal must also receive a favourable vote from both the FIA and Formula One Management (FOM).
Tombazis and the spirit of the regulations
On Thursday during the final week of Bahrain testing, Nikolas Tombazis, FIA Single-Seater Technical Director, explained in detail the reasoning behind the Federation’s initiative:
“When discussing a topic like this, there are many nuances. Maintaining the 16:1 compression ratio was one of the primary objectives when the regulations were discussed with the manufacturers in 2022 and when they were finalised. There is a dedicated article, but it became clear that, as it is currently written, there may be ways to achieve higher ratios.
There has been a lot of noise around this topic, but the FIA has never taken a position stating that someone was doing something illegal. However, if the rules do not fully achieve the original objective, then modifications are necessary to maintain the agreed direction and avoid going in other directions.”
He continued: “We do not want to stifle innovation, but when the regulations state that the parameter must not be lower than 16:1, we are not talking about a completely new combustion system. Certainly, there is no cheating or irregularity involved; it is simply a matter of determining whether it aligns with the intent of the regulations.”
Nikolas Tombazis also explained why an electronic vote was chosen: “We want to close the matter and, hopefully, find a solution. It will not be a unilateral move by the FIA, because multiple votes are required. We will see what comes out of it.”
Another key question posed to the FIA technical chief concerned the timing of the possible regulatory change:
“We were not talking about anything illegal, and therefore it did not seem right to introduce something at the start of the season. We considered this a balanced approach. If the vote is approved, then from August onwards the power units will have to comply with that parameter. And if someone exceeds that level in Melbourne, they will have to make adjustments. But in my view, this issue is not as significant as some people think.”
Finally, Nikolas Tombazis clarified what would happen if manufacturers needed to intervene on their power units to comply with the new checks introduced from August, should they come into force:
“The appendix of the regulations also outlines the procedures for adapting to a regulatory modification. Therefore, if such a necessity arises, we would obviously not prevent them from making changes and then disqualify them. We would allow it.”
This situation underscores the complexities of the 2026 engine era, where the “spirit of the rules” is being tested by clever engineering. While Mercedes currently avoids any formal accusations of illegality, the upcoming vote will determine whether their technical advantage remains a permanent fixture or a temporary loophole to be closed mid-season.
Leave a Reply