Wurz: final test crucial to judge pace

The new FW29 has shone in early running, boosting hopes that the Grove-based outfit can bounce back from their disappointing 2006 campaign, when poor reliability left them down in eighth in the constructors' championship.

But despite the obvious speed of the Toyota-powered car, Wurz thinks that testing so far has been too close to call - and that the final aero packages that will be evaluated by most teams this week could yet mix up the order.

Williams are running at Barcelona in Spain this week, while other teams are evaluating their cars at Sakhir in Bahrain.

"While it is true that we were pretty decent right from the word go and that the foundation is there in order to improve from eighth place in the constructors' championship, it is very hard to judge where this will end," said the Austrian, who is returning to racing after several years as a test driver.

"I find it rather difficult to assess the winter tests. My only conclusion is that the teams are performing pretty closely to each other. It will now depend on who is able to achieve the biggest steps regarding the latest aero configurations.

"Almost all the teams have new aero parts for the latest Bahrain test, some only in Melbourne, and no one can say yet how much they are worth. Furthermore, it will be a question of a team cleverly using the tyres on the specific day."

Wurz is confident, however, that Williams' decision to miss the two Bahrain tests that most other teams have taken part in will not hinder their chances for the start of the campaign.

"Last year it was not much warmer than in Southern Europe," he said. "And the single tyre which has a different construction, is not as critical regarding track temperatures as the rubber in 2006.

"Going to Bahrain has some advantages, but also some disadvantages. You have to handle the logistics, for instance, and if you encounter trouble it is easier to sort that out in Europe than in Bahrain."