Spanish Grand Prix promises to reveal all

LONDON, England (CNN) -- The Spanish Grand Prix will set the tone for the rest of the Formula One season, revealing the most competitive cars for the first time, according to the top teams.

BMW, who lead the constructors' championship, and McLaren, two points back in third, say the race at the Circuit de Catalunya will serve as the "yardstick" for the rest of the year.

They, along with the other teams, spent last week at the Barcelona track testing new developments.

BMW Motorsport director Mario Theissen said the Spanish race was like a "second start to the season."

"The Circuit de Catalunya is one that makes wide-ranging demands and is frequently used for testing by the teams.

"It has often served as a yardstick for their general competitiveness. Here all the teams will be taking a step forward on the development front, us included. Afterwards there will be a fresh assessment of how things stand."

BMW technical director Willy Rampf said he could not "wait to see how things pan out in Barcelona."

"Almost all the teams have been testing improvements to their cars... everyone has made progress, but the key question is, how much compared to the competition?

"That's why it's set to be a very interesting race and one that will also point the way ahead for the coming weeks and months."

BMW driver Robert Kubica said he expected the racing to be a lot more predictable in Spain.

"All the teams know the Barcelona circuit like the back of their hands because we do a lot of testing here. That's why I expect the gaps between the team to become a lot smaller than in the last races."

However, Kubica believed they would be able to get the "maximum" out of his BMW for the first time. Meet this year's drivers

"If we manage that... I'll be racing right up at the front again."

McLaren CEO Martin Whitmarsh said all of the teams had "significant upgrade packages."

"The cars remain relatively consistent over the fly away races [Australia, Malaysia, Bahrain] and this race weekend is the first opportunity to understand how we have moved forward with performance and developed the car in comparison with our primary competitors."

Whitmarsh said the team had focused on aerodynamic performance, developing downforce, balance and efficiency.

McLaren driver Lewis Hamilton said it was difficult to predict what would happen, as all the teams were progressing.

However, they had to get the car's balance right to achieve good high-speed corner performance and traction coming out of the low-speed corners in Barcelona.

Meanwhile, Hamilton's former team-mate, Fernando Alonso, told the Spanish newspaper, El Pais, that there was "never any problem," between the pair.

Alonso also said he would stay at Renault if they succeeded "in creating a winning car."

"The truth is we are making progress. But what I want is to race in a car that can give me victories. There are several, Williams, Toyota, BMW and Ferrari that are always on top no matter what happens." E-mail to a friend

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