May 8 (GMM) Mercedes' Formula One car will look visibly different this weekend in Barcelona, according to Niki Lauda.

And the team's chairman and co-owner is not just talking about the big package of upgrades to mark the start of 2013's European phase.

Frank Schneider, the correspondent for German newspaper Bild, said the major change is "the livery -- more silver, less grey".

Lauda confirmed: "We wanted the car to look even more the 'Silver Arrow'.

"And we believe this is also good for the team because a new look brings new motivation."

More importantly, however, are the changes beneath the paint. For the Spanish Grand Prix, the 'more silver' W04 has a new exhaust, and new front and rear wings.

"During the European season we want to increase by one to two tenths per track.

"We did a good job for the beginning of the season," Lauda continued. "Now it's vital to develop the car faster than the competition."

Some have even suggested Mercedes is the favourite to win in Barcelona, given the car's field-beating form during the pre-season test at the same circuit.

Lauda said: "No, we're not the favourite.

"Pirelli is bringing new tyres and no one knows yet how they work -- they've been very thin with information."