Kobayashi upbeat about Sauber updates for the Spanish Grand Prix

The Hinwil-based team has had mixed fortunes in the first four races of the season, but Kobayashi thinks the team can deliver on its full potential at the Circuit de Catalunya.

"At the Mugello test I definitely had the feeling our new update to the car is a step forward for us," said the Japanese.

"This is good, of course, but only at the Barcelona circuit will we be able to tell how much of an improvement it really is. Not only because testing never allows for proper comparisons to the competition, but also because the Circuit de Catalunya is special."

Sauber's head of track engineering Giampaolo Dall'Ara says that the true benefit of its upgrade is wholly dependent on the amount of progress its rivals have been able to make.

"We tested a major upgrade to the car in Mugello, consisting of a new front wing and new bodywork, including a different exhaust exit and a new diffuser," he said. "The results of the test were encouraging.

"However, all the teams had some upgrades, and only the next race weekend will give us confirmation whether we are able to strengthen our position compared to our competitors. Nevertheless I'm confident that we can have a strong performance in Barcelona."