Raikkonen more comfortable with F2007

Despite winning the season-opening Australian Grand Prix, Raikkonen has complained that he has not felt completely comfortable with the car - especially when running on new tyres.

But he was left full of confidence following last week's test at the Circuit de Catalunya, and chief designer Aldo Costa believes that the step forward was the result of both car improvements and set-up work.

"Yes it's a bit of both," he said. "Kimi is happier with the car, with the modifications done, but he was also working well on the set-up. We were developing a good set-up for him and he is much happier.

"I think he found what he wanted. Of course it depends entirely on the conditions of the track. (On Friday) the track had quite a low level of grip, so it was not a fantastic track, but at the test we were much happier."

Costa says the team have worked hard to fine-tune the settings of the F2007 for both Raikkonen and Massa.

"Every driver is different and every driver likes the car to have a slightly different behaviour. So we must adapt the car in a perfect way, driver by driver, to use the best potential from the driving style point of view.

"There is not a unique style that is absolutely the fastest - any driver has got his peculiarity and we can reach with him his optimum by working with him and adapting the car to his driving style."

But Costa has made it clear that the set-up differences between his two drivers are not huge.

"We are not speaking about big things," he said. "We are speaking about very, very small details, so no day and night differences."