Although Valtteri Bottas gave Mercedes its second win from four in Russia, it was against the run of play and the Ferrari appeared, yet again, to be the more flexible and consistently faster performer.

The red car and the silver are quite closely matched and currently well clear of anyone else, but Ferrari has definitely held the performance edge so far. The Mercedes occasionally has greater peak performance, but the Ferrari can go fast for longer, is more adaptable to different tyre compounds and seems to have a more accessible set-up sweet spot.

It's way too early in a long season to be definitive, but in combination with the way that Sebastian Vettel has not yet lost any points to his team-mate Kimi Raikkonen, who is performing an admirable support role, the SF70-H's traits would seem to have leapfrogged Vettel past Lewis Hamilton as championship favourite.

For Barcelona, Mercedes is planning to introduce an extensively upgraded version of the W08, the first real offensive in what promises to be a heavy season-long development war between the two teams.

The Mercedes has raced in the first four races is 6kg overweight - partly as a consequence of the original gearbox having to be replaced pre-season by a heavier unit.

A reconfigured version of the original lighter gearbox is set to be part of the Barcelona upgrade, along with suspension changes front and rear and a general weight-saving programme that should allow the team to revert to being able to use ballast to vary the weight distribution from track to track.

The fight is on between Mercedes and Ferrari in 2017 but how do they differ technically? Ted and Pat are at the SkyPad to analyse Ferrari’s approach. The fight is on between Mercedes and Ferrari in 2017 but how do they differ technically? Ted and Pat are at the SkyPad to analyse Ferrari’s approach.

There is also a revised power unit in the offing sometime soon. Although Ferrari will surely be extensively developing its car too, on past history Mercedes might be expected to lead the pace in the development war. But what if that is not enough to overcome what may simply be a less good concept?

The two cars are quite different in concept. The Ferrari is significantly shorter in wheelbase and overall length, part of why it is lighter. Mercedes opted, like most other teams, for a very long wheelbase, prioritising having enough length between the front wheels and the beginning of the sidepods - an aerodynamically crucial area.

How the airflow re-attaches around the bodywork ahead of the sidepods after it's been around the blockage of the front tyres determines the effectiveness of the vortices (circulating currents of air) used to speed up the airflow down the side of the car to the rear and over the top of the diffuser.

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The faster this air can be made to flow, the greater the downforce. If there's not enough length between the front wheels and the sidepods it can be difficult to get the airflow along the side of the car moving fast enough.

Ferrari has seemingly managed to get the best of both worlds by maintaining decent length between front wheels and sidepods within a shorter wheelbase. It has done this by beginning the sidepods further back, something made feasible by its interpretation of the 75-degree swept back regulation dimension. Body sections ahead of the sidepods meet that 75-degree requirement without compromising the airflow.

This has been a crucial part in allowing Ferrari to make a more compact and lighter car.

The greater bodywork area of the longer Mercedes probably creates more peak downforce - something that appears to enable it to run with a lower rear wing angle than the Ferrari at most tracks, for better straightline speeds - but the extra weight and how that has locked in a pre-set weight distribution has made for a car that is generally harder on its tyres and with a narrower set up window.

The question is whether these traits can be cured by an update or whether they are inherent to the concept. We have to wait another few days to get the next installment of this fascinating struggle between the two heaviest hitters in F1.

Also, let's not forget what is promised to be radically different, Adrian Newey-directed update for the Red Bull too.

In the early stages of these new aero regulations the form book is still thrillingly volatile.

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