"Across all our teams we have covered a lot of mileage," said Renault F1's head of track operations Remi Taffin, following today's two sessions, "more than 2,300km - equivalent to one race distance per car, and collected a lot of information that we can use for the rest of the weekend. Compared to where we were just one month ago, this is clearly a big step forward in reliability, although we are still not where we want to be in terms of performance.
"We saw a big drop in temperatures between the first and second session, in the order of around 10°C track and ambient temperature. While this has not necessarily affected the PU set up or maps used, it does have an impact on the cooling level and inlet temperatures so it's something we have to monitor very closely to stop any issues occurring.
"There have been a lot of positives from today. The pace of the Red Bulls on the longer runs is strong and we had no major issues. Both Lotus cars were also able to complete a lot of mileage. Romain reported a misfire in FP2, which we later traced to a problem with the wastegate. We will fix this overnight to work on pure performance with the team tomorrow.
"Toro Rosso again had a strong day in the top 10. The only issues were relatively small: an oil leak in FP1 and then issue on the wastegate for Daniil in FP2, but once both were identified they were easy to fix and did not impact the programme.
"For Caterham it was again a day of two halves. While Kamui's car worked fine, there were problems on the ERS and then MGU-K on Marcus' car, which ultimately put paid to his day in FP2. We'll change the parts overnight to hope for a better day tomorrow.
"Overall however it's been a productive day with lots of data and mainly clean running, which means we can look to work on performance tomorrow."
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