Kimi Raikkonen says Jerez laptimes are less important than his initial feelings in the Lotus

The 2007 world champion played down his headline-grabbing fastest time at the Spanish circuit after ending up 0.1s faster than Paul di Resta's Force India, having completed 73 laps on a relatively trouble-free day.

"It makes no difference," he said when asked how it felt to be quickest on his return to contemporary F1 action. "I mean it's the first day, and it would make a difference if it were a race weekend, but here it means nothing."

But the Finn said that the information he gained using 2012-spec equipment and proper race tyres - as opposed to the demo rubber he had used prior to Tuesday's official running - was hugely valuable as he continued to reacclimatise to the sport.

"The feeling is pretty OK with the car and for sure I've had much worse first days and worse feelings with new cars," he added. "I was quite happy with it."

"The feeling was pretty good with the car. The first feeling is handling quite nicely so... just going with that feeling I'm quite happy, but there are areas that we can improve and that we have to improve. I'm positive about it."

Raikkonen completed 60 laps before the team broke for lunch, and during that morning he completed four stints culminating in a 1m19.670s lap - faster than Rubens Barrichello's best overall time of 2011.

And while Lotus's afternoon was interrupted by the need to change a KERS battery, Raikkonen said he was pleased with the ground he had covered on the first day.

"I did exactly what the team were planning, or not exactly because we missed a few laps when we had a small issue," he said. "We tried different things, we did a few checks.

"But we did also quite a lot of the normal things you have to do on a first day yesterday, so that was a help to get rid of those. But it was a pretty normal first day."

Raikkonen added that he had been pleased with how the tyres had felt: "They are what they are and you try to get the best out of them.

"When they are new they seem to be pretty nice tyres. Of course they probably go away more than in the past, but it's the same for everybody and in a long run you try to save them as much as you can and get the best out of it."