Romain Grosjean led the charge for Lotus on Friday during practice for the Brazilian Grand Prix.

Grosjean was seventh quickest in the opening session, on a 1 minute 14.719 seconds, and in the afternoon he maintained his place in the top ten, finishing up ninth on a 1m 14.994 seconds.

Speaking at the end of the day and after completing 70 laps, the Frenchman was especially encouraged by his long run pace, although he admitted that the team had hedged their bets given rain is predicted on race day.

"It was a very hot and sunny day which wasn't so easy for the tyres as it was difficult to get them to work properly so we struggled a little bit. Speed was not especially easy to find, but we ran through our normal programme with a little bit of focus on a wet set-up as we know there's rain forecast for Sunday," Grosjean confirmed.

"We only ran a little with the 2013 tyres in the morning; my initial impression is that they feel a bit better and you can notice they have a different construction. Our long run pace was good though so let's see what we can do tomorrow."

Kimi Raikkonen meanwhile had a more challenging day in the sister car with an ignition coil issue costing him some track time in the morning. However, he wasn't too concerned, even if he was only 16th quickest in FP1 and 12th in FP2.

"We had a problem in the morning but it's just one of those things; you don't want it to happen, but it's not the end of the world," said Kimi. "It's unfortunate it took a while to fix as we missed time on track. Other than that, it was a very normal Friday for us.

"It was quite difficult to find a good set-up so we tried quite a few things. Tricky is usually the way for our Friday's and we've always been able to find a better set-up for Saturday so that's exactly what we'll try to do for tomorrow."

"We've had an encouraging start to the weekend," was how Lotus trackside operations engineer, Alan Permane summarised the day. "Although Kimi's track time in FP1 was restricted, Romain completed some interesting back-to-back comparison runs with Pirelli's 2013 development tyre which looks to be a few tenths quicker than the current configuration even on this year's car.

"Kimi had some catching up to do in the afternoon and struggled initially on the prime tyres, but with a few balance tweaks to accommodate the soaring track temperatures and his engine now running as it should he settled down to put in some decent runs. The track temperature was around ten degrees higher than in the morning - one of the hottest Friday's we've seen all year in fact - and therefore yielded less grip.

"Despite this however, our long run pace with Romain looked very competitive. We also ran differing setups in anticipation of a potentially dry qualifying, wet race scenario, so there's a lot of data to look at overnight but overall we're pretty pleased."