Carlos Sainz is confident Mercedes will deliver a competitive engine for the new F1 rules in 2026.
The 2026 F1 engine regulations will introduce a new generation of hybrid power units with a focus on sustainability and cost efficiency.
These will be run on sustainable fuels, a dramatic change that should see a major shift in priorities.
A team’s competitiveness seems to be related to the strength of its power unit.
As a result, the latest paddock rumors suggest Mercedes could start 2026 with its best engine.
In an interview with El Partidazo de COPE, Sainz admitted that the Mercedes engine was a key factor in his decision to join Williams this year.
“Yes, I have great confidence in the Mercedes engine,” he said.
“In fact, that’s one of the main reasons why we chose Williams for this new regulation change. We knew we would use a Mercedes power unit and everything we heard about it was and remains positive.”
Mercedes supplies engines to McLaren and Alpine.
Sainz stressed the need for Williams to provide a strong chassis, as four teams operate it.
The Spaniard also does not want to rule out the possibility of Aston Martin and Ferrari using Honda engines.
“But of course we have to remember that Mercedes has Mercedes engines, McLaren has them, Alpine has them and Williams has them too,” he added.
“There are already four teams and eight cars using the same engine, and two of them, McLaren in particular, are the best at the moment.
“So no matter how good the engine is, you have to get everything right with the chassis. And of course Honda and Aston Martin are competitive and Ferrari is always there. Ferrari is always in the fight.”
2026 engine ‘completely unknown’
Williams boss James Vowles played a key role at Mercedes during its dominance at the beginning of the V6 hybrid era.
While Mercedes started 2014 with a dominant engine and this was the main reason for their success, Williams benefited from this, finishing third in the constructors’ standings in 2014 and 2015.
James Vowles, Williams
©XPB Images
Vohles admitted that no one really knows yet whether Mercedes is ahead of its rivals.
“The story in the paddock is interesting because no one knows about it. It’s just the facts behind it,” Vowles explained.
“It’s not like all the (power unit) manufacturers got together with some cards, top trumps, and said, OK, I’m here about power, I’m here about electrical, I’m here about weight, I’m here about cooling efficiency.
“Mercedes has always done well with regulation changes because they are ahead of the curve and are investing ahead of the curve. There’s no doubt about that. But the reality behind that is we don’t know what Ferrari is getting or what Honda is getting.
“It’s a total unknown at the moment. So we’re really happy with the job that we say they’ve done in terms of preparation and development, but until the lights go out in Australia, nobody knows.”