Mercedes are the F1 team to beat in 2026, but why are they so fast?

Mercedes are going to be in a battle for both F1 championship titles this year, and not just because they looked good in testing.

Their pre-season testing performance at the private shakedown in Barcelona last week was impressive, putting in over 500 laps during the first week of testing, and topping the timesheets on two of the three days that they were running.

But Mercedes were already quietly confident that they had built a monster, and George Russell said as far back as October that he felt like his best chance of winning the drivers' championship in 2026 was with Mercedes.

Russell's interviews last week were also very positive, with he and team-mate Kimi Antonelli issuing glowing reviews of their new W17 machinery.

But why are so many pundits and fans already tipping Mercedes to be the dominant team in the sport in 2026?

F1 TESTING RESULTS: Barcelona shakedown times as Hamilton roars back

Clever diffuser adaptation

One visible part of the W17's design during testing in Barcelona was a rather gaping hole in the diffuser.

This unusual opening had not been on their original renderings when revealing their 2026 livery, but close up pictures of the car from the Barcelona shakedown reveal that it is indeed there.

The idea of the hole in the diffuser is that the W17 deliberately channels the airflow through this hole. The additional air, which expands in the rising underbody, generates even more downforce.

It's a design technique that Ferrari and Red Bull seem to have opted for too, although Red Bull's is a completely different shape, with the diffuser wall in the rear section appearing to be completely absent.

Defending champions McLaren do not have that hole in the diffuser, although of course it is a simple tweak to make should the teams with this quirk end up being the teams to beat.

Mercedes' engine 'trick'

Of course, part of the reasoning for fans and pundits bigging Mercedes up is because of their history at maximising past power unit regulations, with their engine dominating the sport following the wholesale rule changes in 2014.

Mercedes claimed eight consecutive constructors' championships in the early years of the hybrid era, between 2014-2021.

And this winter has been filled with rumours that Mercedes have found a 'trick' in their new power unit that could be worth up to 0.3 seconds per lap.

The alleged trick regards the geometric compression ratios, with it being reported that Mercedes have found a way for the compression ratio to be at the allowed 16:1 when the engine is stationary, but then increase to the previously allowed 18:1 when moving, something that could allow an extra 15 brake horsepower.

Time will tell as to whether Mercedes really have found this extra pace or not, but the Brackley outfit are looking in good shape to be able to mount a title challenge, at least challenging closer to the likes of McLaren than they were last year.

F1 HEADLINES: Christian Horner declares ‘unfinished business’ in F1 as Red Bull warned of Max Verstappen exit

Related