As previewed by Sky F1 columnist Mark Hughes, world champions Mercedes, stung by their defeats to Ferrari in Australia and Bahrain, have delivered an extensively upgraded W08 for Barcelona. The updates include a lighter gearbox as part of an overall effort to reduce their car's weight and suspension changes to the front and rear.
The scoop-style vanes have been attached to the front wing of the W08 for the Spanish GP with further changes made to the rear of the car and around the bargeboards. The nose of the car has also been trimmed.
"The scoop is taking air and working it through the intricate bargeboards, and into the side bargeboards and out towards the diffuser at the back of the car. It's an innovation I've never seen on a modern Formula 1 car," analysed Sky F1's Ted Kravitz.
However, it appears Mercedes have not quite been able to engineer all of the excess weight out of the W08 just yet. "We have managed to make some decent steps but we are not yet where we want it yet," team chief Toto Wolff said. "We are not there yet [at the stage of moving ballast around]."
Nonetheless, the significant Mercedes upgrade is the first salvo in what is expected to be a year-long Development War between Ferrari and the Silver Arrows in their battle for overall supremacy.
A case of 'if it ain't broke, don't fix it?' for Ferrari? At the head of the Drivers' Championship, and just one point behind Mercedes in the constructors', it has been far harder to spot the additions to the SF70-H since Russia.
"The only thing that I can really notice is the change in T-wing," said Kravitz. "Kimi Raikkonen tried it out in Practice One and it has no less than four elements, two at the top and two underneath it.
"It's a nice development of something Williams and Mercedes initially ran and it seems to be working so far. But, apart from that, there's not too much."
There are likely to be further tweaks under the surface too with Sebastian Vettel, who ran the new T-wing in Practice Two, telling Sky F1: "I don't know who brought the most updates but it's about who brought the best."
Would it effectively be a brand new car? Or the B-spec RB13? Well, Christian Horner has described the wholesale additions to Red Bull's car at Barcelona as a "development" of the RB13 that ran relatively disappointingly in the season's opening flyaway rounds.
"It's predominantly aerodynamics," the Red Bull chief told Sky F1. "So you'll see around the mid-car area, the bargeboards and so on, it's quite significantly different. Then that rolls into floors and sidepod areas as well, so it's a collective number of parts."
The new parts include revised endplates front and rear, with a new-look bargeboard and diffuser also part of the package.
Force India, like Mercedes, have been keen to shed some weight from their 2017 car and the addition of aero upgrades which started in Russia has continued at Barcelona.
In Practice One, the VJM10 featured a revised front wing with tweaks to the cascade area. "What we've seen so far is promising," said team chief Bob Fernley.
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