Piastri’s Mercedes admission ahead of Miami engine tweaks

Oscar Piastri has denied Formula 1’s engine tweaks could benefit Mercedes’ customer teams, after all, the “bigger piece of the puzzle” is the chassis, not how they are working the engine.

Although reigning world champion McLaren continues to run as a Mercedes customer team this season, eyebrows were raised at the season-opening Australian Grand Prix when the MCL40 came up short against its Mercedes counterpart.

Oscar Piastri offers blunt McLaren reality check

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Introducing a new power unit formula this season, McLaren team principal Andrea Stella acknowledged that the team had expected closer performance parity when using identical power unit hardware.

“We have work to do to exploit the potential of the power unit, which, once I see the potential that HPP [Mercedes High Performance Powertrains] is extracting, looks like there’s more that is available,” McLaren team principal Andrea Stella said.

He added: “What they are doing shows they understand a lot more, and maybe the flow of information hasn’t been as anticipated.”

Stella revealed that McLaren had already raised its concerns with its engine supplier.

“The discussion with HPP about having more information has been going on for weeks,” he said. “Because even in testing, we were pretty much going on track, running the car, looking at the data and, ‘oh, that’s what we have — good, now we have to react to what we have’…

“I have to say, since we are a customer team, this is the first time that we feel we are on the back foot even when it comes to the ability to predict how the car will behave and the ability to anticipate how we can improve the car.”

Three races into the F1 2026 season, the regulations regarding energy management with the new engines has been tweaked.

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The FIA announced a “number of refinements” to the regulations, relating to qualifying, the grands prix and the race starts.

In qualifying, there is a reduction in the maximum permitted recharge from 8MJ to 7MJ, while peak super clip power increased to 350 kW.

During the grands prix, the maximum power available through the Boost will be capped at +150 kW. The MGU-K deployment will be set to 350 kW in key acceleration zones (from corner exit to the braking point, including overtaking zones), but limited to 250 kW elsewhere on the lap.

There are also changes for the race starts with a new ‘low power start detection’ system developed that will trigger an automatic MGU-K deployment to mitigate the risk if a driver makes a slow start.

But while Piastri would love it if the tweaks worked in favour of Mercedes’ customers by reducing some of the extremities around energy management, he concedes McLaren’s deficit to Mercedes is largely chassis related.

“I would love to say yes, but I don’t really think so,” he told PlanetF1.com and other media outlets during McLaren’s spring debrief.

“I think Mercedes, they had a better understanding of the power unit and how to get the most out of it.

“I think in Japan, certainly on my side, obviously it was a pretty compromised weekend on Lando’s side, but on my side of the garage, I thought we did a really good job of maximizing everything from the power unit to the car that we had.

“But we’re clearly still a fair way behind on, you know, just downforce and performance from the chassis as well.

“So, you know, I’m sure that gap in the power unit understanding will close a little bit, but our biggest deficit in Japan was not that we were lacking time from the power unit, or how we exploited it, it was that our car wasn’t as good as theirs.

“So, yeah, I think that’s the bigger piece of the puzzle.”

McLaren has been working hard on upgrading the chassis, finding downforce and performance during the break between Japan and Miami.

So much so, Stella says the MCL40 will be an almost entirely new car with major upgrades in Miami and Canada.

“In our intent, there was always the idea to deliver sort of a completely new car especially from an aerodynamic upgrades point of view for the North American races,” he told PlanetF1.com and other media during the team’s spring debrief, “so we could keep up with this plan.

“Obviously, the fact that the calendar has been changed helped a little bit – like I’m sure it helped all the other teams that could work more streamlined towards upgrading the car, rather than being busy with racing.

“But I could say overall that across Miami and Canada, we will see an entirely new MCL40.”

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