‘What’s off limits?’ – F1 warned dangerous precedent risked in compression ratio saga

The possibility of late power unit regulations changes opens up a worrying can of worms if successful, believes Alpine’s Steven Nielsen.

Four of the five power unit manufacturers are attempting to get the regulations changed to introduce a new compression ratio testing mechanism to tighten up a grey area that Mercedes is believed to have exploited.

Steve Nielsen: Power unit regulations are ‘crystal clear’

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The first Bahrain test was dominated by discussions related to power unit compression ratios, ahead of the homologation cut-off for the new units on March 1st.

On that date, the five power unit manufacturers are required to submit all their documentation regarding their unit’s architecture and construction to the FIA, but a complication has emerged about whether or not the alleged Mercedes design will be deemed legal.

This power unit is believed to be able to run at a compression ratio in excess of what the regulation states, a situation that is not being denied by the likes of Mercedes team boss Toto Wolff. However, this doesn’t mean the unit is in breach of the regulations, thanks to the wording used in the documents.

Under the current wording, the grey area Mercedes is said to have exploited appears to exonerate the Brixworth-based manufacturer of any wrongdoing.

Article C5.4.3 states that, “No cylinder of the engine may have a geometric compression ratio higher than 16.0.”

While seemingly straightforward, the same regulation continues on to state that, “The procedure to measure this value will be detailed by each PU Manufacturer and executed at ambient temperature.

“This procedure must be approved by the FIA Technical Department and included in the PU Manufacturer homologation dossier.”

It appears as though four of the five power unit manufacturers [PUMs] have interpreted the rule based on the seemingly straightforward terminology of the first line, while Mercedes has interpreted it based on the regulations’ sentences as a whole, ie. based on the measurement criteria being a critical factor that influences the first sentence.

Early reports on the topic suggested that Red Bull Powertrains [RBPT] had also discovered ways to adhere to the geometric compression ratio of 16.0 in ambient temperature testing, whilst also being able to run at a higher ratio at higher temperatures, but swapped to join the other three PUMs and isolating Mercedes on the topic.

Under the governance structure, the Power Unit Advisory Committee [PUAC] takes priority on this, and not the F1 Commission which is primarily made up of the teams.

The PUAC consists of the five PUMs, as well as the FIA and FOM, with several meetings having already been held to discuss the topic. It’s understood that another meeting is set to be held at which a critical vote amongst the seven parties is likely to be held.

PlanetF1.com understands the situation is that the four non-Mercedes PUMs have proposed a compression ratio test at hotter temperatures, and will present the specifics of this test at the next PUAC meeting. If a supermajority is established via vote, meaning all parties except Mercedes, a regulation change can be made and ratified by the World Motor Sport Council.

If the four PUMs succeed in convincing the FIA and FOM such a test is needed and the regulation wording tightened, this would obviously leave Mercedes in a highly precarious position ahead of the homologation date as its power units may need reworking in order to conform with the new terms of the regulation.

As for how much of an advantage the ratios offer, Wolff hinted at it being as inconsequential as two to three horsepower, although Max Verstappen scoffed this figure and suggested it could be 10 times those numbers.

Mercedes High-Performance Powertrains [HPP] is understood to have actively communicated with the FIA through its design process, but, with Mercedes as a PUM now on its own against the other four PUMs, the matter has moved into the political arena.

The FIA and FOM’s votes will determine the outcome of whether Mercedes can continue as it is, which risks team protests in Australia, or has to make late revisions if the four PUMs successfully manage to get a rule rewritten in their favour after, seemingly, failing to spot a potential opportunity.

“Politics and F1 are… it’s kind of new, but not really. It’s a big regulation change,” Alpine managing director Steven Nielsen said on the topic in Bahrain on Friday.

“Some people have gone down one route, other teams have gone down another.

“My personal view is that I’m not concerned about it, because I think the regulations are crystal clear on when the compression ratio is measured.

“Some other people are trying to introduce different parameters to that. That’s for reasons best known to themselves.

“We’ve got full confidence in Mercedes. They’ve built a PU in good faith with a very clear set of regulations, we’re happy with it, and we trust the governing body to do the right thing.”

Powered by Mercedes, Nielsen’s team may be one of the four affected if the four non-Mercedes PUMs succeed in their lobby.

Since 2017, Nielsen worked in sporting director roles at FOM and the FIA, playing an active role in helping shape the regulations and their wording, before returning to the grid with Alpine late last season.

With his recent experience in governance, Nielsen said his concern from this matter is that the ramifications, should Mercedes lose out, could be more broadly felt in other areas of the regulations in future.

“It’s not so much about the current issue but the more fundamental thing for me is the way we’re going about it,” he said.

“If we’re saying that a very clearly set of regulations written set of regulations can be challenged in this way, then what else is off limits?

“Everything’s up for discussion. If a certain set of teams don’t like something that’s very clearly written, if suddenly you can have a lobby group and change it, then then you’re in a whole different world.

“People invest an awful lot of time and money, particularly money, into this, in good faith.

“If suddenly we’re going into a world where everything can be challenged, even though it’s clearly written, for any reasons other than safety reasons, then I think that’s a whole new world which we’ve not been in before.

“The compression ratio discussion is one thing, but I think it’s very clear. You could say I’m biased because we’ve got the Mercedes engine in our car, but that’s honestly what I believe.

“But I think the more fundamental question is, do we really want a sport where clearly written stuff can just be challenged because people fancy doing it? That’s for the FIA to answer.”

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With the four non-Mercedes PUMs essentially challenging the FIA’s wording of the regulations in light of Mercedes’ different interpretation of the same Article, the possibility is that the matter is unsolvable before the season-opener in Australia.

With mixed messages coming from the teams and manufacturers about the next steps in the PUAC process, a process that is not made public in the sport’s rules, the possibility remains that the teams line up in Australia with the power units as they are now, having been homologated in their current configuration.

Should that happen, it will depend on the non-Mercedes-powered teams on whether they wish to lodge a protest against the Mercedes-powered cars.

With a protest now costing a complainant 20,000 euro on deposit to lodge, Nielsen said taking such an action would force the issue to be addressed.

“I guess they’ve got their right to protest, I suppose – go to Melbourne, if they really feel that strongly, then put some skin in the game and do something about it,” he said.

“I don’t know whether the FIA will express a view on this before Melbourne. I kind of hope they do. Because I kind of hope the story in Melbourne isn’t about compression ratios.

“We’ve got lovely new cars, it would be lovely if the story was about that rather than compression ratios.

“But those of you that are old, like me, you’ll remember the double-diffuser story in Melbourne before with the BrawnGP car [in 2009].

“So these types of stories, they come up every now and again, particularly with big rule changes.”

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