Heikki Kovalainen said there is still more to come from Caterham despite an impressive performance on the second day of testing in Barcelona.
The Finn returned to action having been forced to miss the opening day of running with food poisoning, with Vitaly Petrov having stepped in for Thursday's action.
Although admitting he still didn't feel 100 per cent, Kovalainen was able to post the fifth fastest time at the wheel of the CT01, just 1.2secs off the pace set by Romain Grosjean.
Despite the encouraging performance, Kovalainen said he felt there was still more to come after a 'good day' in the office.
“I'm pleased with how today has gone,” he said. “I'm still not quite 100 per cent after a bit of food poisoning kept me away from the track yesterday, but I'm pretty much over it and the way today has gone is good news.
“We keep going in the right direction and seem to have put the little issues that were holding us up behind us and the number of laps we've now run means I'm starting to be able to fine tune the setup and find a balance I'm really happy with.
“There's still more to come in outright pace and we'll work more on that tomorrow, but I think we can say this has been another good day for the whole team.”
Caterham Group chief executive officer Riad Asmat was also pleased with the performance of the car.
“Another very good day, and signs that we are starting to find out what this car can do,” he said. “The team have worked very well today and apart from a minor issue this morning we have run faultlessly and have shown pretty good pace, so I think we can be pleased with what we have achieved today.”