Romain Grosjean went seventh fastest whilst Kimi Raikkonen set the twelfth fastest time during a hot opening day of the Brazilian Grand Prix weekend at Interlagos, Sao Paulo.

Both cars ran with the latest specification exhaust system as raced for the first time in Austin, as well as new front drums. An issue with an ignition coil shortened Kimi's running in the morning session.

Kimi's car suffered an ignition coil issue in FP1 which was resolved during the session. Both drivers trialled the 2013 Pirelli development tyres during FP1. In FP2 we ran the 2012 spec hard and medium compounds. We trialled new front drums on both cars and the latest front wing upgrade on Romain's car.

Our long run pace in hot temperatures looks to be good. The car looks to be strong in both high and low downforce trim.

Kimi Raikkonen: "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. 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."

Romain Grosjean: "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 today, 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. 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 so let's see what we can do tomorrow."

Alan Permane, Trackside Operations Director: "We've had an encouraging start to the weekend. 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."

Check out our Friday gallery, here.