Carlos Sainz drops new Mercedes F1 2026 engine clue with Williams admission

Revealing the Mercedes power unit was one of the “main reasons” he chose Williams, Carlos Sainz concedes Williams also has to do its part with the chassis for the all-important F1 2026 reset.

Informed by Ferrari last year that 2024 would be his final campaign in red as the team had instead signed Lewis Hamilton, Sainz spoke with almost all the teams up and down the grid as he sought to secure his Formula 1 future.

Carlos Sainz: That means we have to get everything right

Sainz went with Williams despite the team’s recent struggles and signed a multi-year agreement that would continue into F1 2026 when the sport undergoes its biggest regulatory reset in its history.

The engine regulations will be reset as Formula 1 adopts more sustainable and efficient engines that will run on a 50/50 split between combustion engine and electrical power, a 300 per cent increase from the current battery impact.

The last time Formula 1 introduced new engines, Mercedes came to the fore to record seven Drivers’ titles on the trot and eight Constructors’ crowns.

That, Sainz revealed, played a part in his decision to sign with the Mercedes-powered Williams team.

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“Yes, I have a lot of confidence in the Mercedes engine,” he told El Partidazo de COPE.

“It’s actually one of the main reasons I chose Williams for this new regulation change. I knew we’d be running the Mercedes power unit, and everything I’ve heard about it has been positive, and still is.”

But, of course, it’s only about the engine.

Next year, the chassis regulations will also change with smaller, lighter, more agile cars that use active aerodynamics.

Sainz says as important as it is for Mercedes to get the engine right, Williams needs to deliver on the chassis as there will be four teams powered by Mercedes.

“But of course,” he continued, “we can’t forget that Mercedes will have the Mercedes engine, McLaren will have it, Alpine will have it and so will Williams.

“That’s already four teams, eight cars, with the same engine, and two of those teams, especially McLaren, are superior right now.

“So, no matter how good the engine is, you still need to get everything right with the chassis.

“That means we have to get everything right with the chassis to stand out.”

However, he doubts the battle will be solely between the Mercedes-powered car with Sainz highlighting Ferrari and Aston Martin as teams who could make gains with the power units.

“And of course, Aston Martin with Honda will be competitive, and Ferrari will always be there. Ferrari are always in the fight,” he said.

The Spaniard is dreaming of a bright future with Williams, which currently sits P5 in the Constructors’ Championship with Sainz having added 15 points to the team’s tally with his third-place finish at the Azerbaijan Grand Prix.

“Williams has moved up from ninth to fifth this year, that’s a huge step forward,” he said. “In Formula 1, gaining four positions from one season to the next means you’re doing things right.

“Next year, starting to win races might be difficult, but I think we can fight very closely with Ferrari, Mercedes, Red Bull and company.”

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