Nico Hulkenberg says the adaptability of Force India's VJM05 added to his feeling of optimism after topping the times following the second day of preseason testing in Barcelona.
The German ran at the sharp end of the field throughout the day, before establishing himself at the front after changing to Pirelli's super-soft compound in the final stages of the morning running.
While Hulkenberg admits he was pleased to register a good time, he said he was also encouraged by the VJM05's baseline setup and its resulting ability to adapt to different compounds.
"It was a pretty good day – we had good speed and we were also able to try all the different compounds, run on all of them and get a good idea of how our car reacts," Hulkenberg explained. "We have a good baseline, I think. As always, you play with the wing a bit from one compound to another, but we have good knowledge now of how the car reacts and it's pretty good."
When asked about his run on the super-soft compound, seen for the first time on Tuesday, Hulkenberg added: "You always aim to do good laps – we're race drivers, you have to drive fast and push the car to the limit to see where the weaknesses are.
"It seems to be a classic qualifying tire – at least it was yesterday. It's softer rubber which gives you additional grip for one lap. We had to try it at some point to see how the car reacts to it; now we have good experience of that and we can move on.
"We got a lot of laps [on Wednesday] and did some constant speed runs, some aero work and some data gathering and gained a lot of good knowledge. Once again the car has proven very drivable."