Jarno Trulli, Team LotusLotus driver Jarno Trulli described the team's first day running its new exhaust blown diffuser as "positive."

The Italian continued to struggle with the power steering problems that have blighted Lotus since the start of testing, but despite having a hard time finding the right balance, the Italian is confident that the upgrades, which also include aerodynamic tweaks, are a major step forward.

"It was pretty positive as a first day," Trulli told AUTOSPORT. "There is some work to do to get the best out of the new aerodynamic package, so today was all about collecting data. We didn't have any problems with it, so it was a good day."

The Italian added that the team's main focus has been on adapting the car's setup to work best with the new blown diffuser in order to maximize the effect of the new design.

"It's all about trying to find the right ride height to run the car in the spot where the aero works. We need to learn the car and then use the engine properly to blow the diffuser."

Trulli's teammate, Heikki Kovalainen, ended today's running just three tenths off the midfield pack. It is hoped that the upgrade will be worth a second per lap, allowing Lotus to break into the midfield on raw pace for the first time.