Neither of the Sauber F1 Team drivers, Kamui Kobayashi and Sergio Perez, was happy with their car's set up on the first day of practice at the Hungaroring, which took place in changeable weather conditions.

In the morning's 90 minute session both drivers spent half of the time working on aero measurements. They compared different downforce levels, Kamui also did a rear wing comparison, and each of them was using just a single set of the medium compound tyre, which for the Hungarian Grand Prix is the harder choice.

For the afternoon the focus was on set-up work and tyre evaluation. However, halfway through the second session it started to rain and neither driver was able to complete his programme as planned. Kamui did a few laps on soft tyres before the track became wet, while Sergio had no chance to run them because a technical problem had to be fixed first.

Kamui Kobayashi: "The weather today was a kind of surprise. We had such a packed programme and I really would have preferred two dry sessions, because we still have a lot of work to do. For some reason we struggled in the morning. We don't understand our poor performance in dry conditions yet and have to investigate that. We were fast on the wet track but I think that is not worth anything when I look at the weather forecast."

Sergio Perez: "It was a difficult day. I am not happy yet with my car. We need to look at the data now and we need a good third free practice session tomorrow. However, on the time sheets it looked particularly bad for me in FP2 because I didn't manage to go out on soft tyres after a brake problem needed to be fixed in the garage."

Giampaolo Dall'Ara, Head of Track Engineering: "The session was not the easiest to manage with the rain. Overall there's quite a lot of work for us to do with regard to performance as well as reliability. We had some reliability issues on Sergio's car, which cost him some running time. It was easier here to get the intermediates tyre to work than in Hockenheim, but also here half of the track was quite dry. In completely dry conditions we are definitely not where we want to be with regard to the lap time, so we have to analyse all the data tonight and draw the right conclusions."

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