Sainz explains ‘biggest change’ at Williams as he predicts how long it will take to adjust to new car

Carlos Sainz has identified adapting to a new power unit as the “biggest change” he has faced since joining Williams, with the former Ferrari driver set to race with a Mercedes engine for the first time in his F1 career.

Sainz is no stranger to changing teams, having raced for Toro Rosso, Renault, McLaren, Ferrari and now Williams during his 10 years in the sport so far. While the Spaniard acknowledges that this may bring advantages and disadvantages, he believes that a positive comes from gaining an insight into different working cultures.

WATCH: Sainz, Albon and Vowles unveil Williams’ new car livery for 2025 at F1 75 Live

Whilst speaking to media at the F1 75 Live event, Sainz was asked about how different life at Williams is compared to the previous teams he has competed for, leading the 30-year-old to joke: “I like blue, first of all – it’s an easier colour to combine with other things!

“Apart from that, yeah, that’s me [having raced for] 50 per cent of the teams in Formula 1 in 10 years. That’s a different team every two years, I don’t know if it’s a good or a bad thing!

“But it definitely has given me a lot of experience and a lot of information of how different teams work, [how] different organisations can work and different cultures. Definitely this is the biggest switch, from an Italian base back to a British-based team.

ABU DHABI, UNITED ARAB EMIRATES - DECEMBER 10: Carlos Sainz of Spain driving the (55) Williams FW46 — Sainz first got behind the wheel for Williams during the 2024 post-season test in Abu Dhabi

“It’s definitely going to be a big change but nothing that I’m not used to, nothing that I haven’t seen before and [it’s] obviously a good challenge that I am excited for, [to] enjoy and keep [being] patient as much as possible. I feel good, I feel at home, which is important.”

However, when pushed on the challenge posed by using a Mercedes power unit for the first time, Sainz explained: “I can talk a bit about [the post-season test in] Abu Dhabi and how [those] first laps went. Definitely I think [the thing] you feel the most when you change teams, the moment there’s a power unit involved, is the power unit.

GALLERY: Williams present livery for their FW47 at F1 75 Live season launch

“The noises, the vibrations, the sound – everything just changes completely, so even if I went out of the pits trying to understand the aerodynamics and the tyres and the feeling on the mechanical side of the car on the aero, the only thing I had to adapt in the first few laps was how different a power unit can be, so that’s probably the biggest change.

“Also the way the power unit operates in terms of switches, switch changes which nowadays in Formula 1 with so much going on our steering wheels with the deployment, the battery, things like this, safety procedures of the engine and the power unit – it’s all definitely the biggest change that I’m having to adapt [to] so far in Williams.”

In terms of how long it may take for him to adjust to the FW47, Sainz admitted that having only limited chances to do testing means that the process takes more time.

LONDON, ENGLAND - FEBRUARY 18: Carlos Sainz of Spain and Williams with James Vowles, Team Principal — Sainz joined team mate Alex Albon and Williams Team Principal James Vowles to unveil the squad’s 2025 livery at F1 75 Live

“Normally from my experience, that adaptation process – with only three days of [pre-season] testing, which is one and a half [days] per driver – my experience tells me it takes around half a year to really understand all the tricks and the little details on the car,” the four-time race winner said.

“If testing would exist [more], that process would be a lot shorter. There’s so many things that you need to go weekend by weekend learning and experiencing. This doesn’t mean that you can’t be competitive – I believe that if you are good at adapting and you do a good winter with your team, you can be competitive straight away.

TEAM PREVIEW: Can Sainz’s arrival help Williams take the next step on their journey in 2025?

“But there’s always the last tenth or the last two tenths of the car that you learn as the year goes by and you start to work better with your engineers, better with the team, and you start instructing performance not only from your side of the car but also from everyone around you, all your engineers from different departments.

“You just try to start maximising everyone to your advantage. Again, it doesn’t mean that I cannot be competitive or we cannot be competitive straight away, but really, really extracting that last tenth of the car always takes a bit of time.”