On a day when a couple of teams, including McLaren and Renault, brought their 2007 testing programme to an end, BMW's Robert Kubica gave the German team another major confidence boost by topping the timesheets.

Along with Kubica, the German outfit had Nick Heidfeld on duty, who completed his third and final day of testing, Both drivers continued the team's development work on the electronics and car set-up for 2008. Also, the Pole had his first taste of the 2009 Bridgestone slick tyres. While there were a few small issues that caused minor interruptions to the planned test, all in all it was a positive day the team claims.

Tomorrow's work will focus on 2008 developments, while the team is hoping to finish its mileage and tyre allocation for the year. For Kubica it will be his third day of testing, while Marko Asmer will have a full day, after the Estonian spent a half day in the car on Tuesday.

McLaren concluded its 2007 programme, as the test team continued to focus on the programme of aerodynamic and suspension work. Both Lewis Hamilton and Pedro de la Rosa completed the planned programme in another constructive session. The Spaniard also spent time on slick. In order to simulate the 2009 conditions as much as possible, the car was also set-up to the corresponding aerodynamic regulations. This sees the cars run with less downforce.

Felipe Massa and Michael Schumacher took to the track for Ferrari as they mainly worked on the development of new components and electronics in preparation for next year. In addition, in the afternoon, Schumacher ran with slicks.

At Red Bull, David Coulthard and Mark Webber swapped cockpits, so that the Scotsman was in the car with the 2008 specification ECU, while his Australian teammate drove the 2007 car with traction control and engine braking disabled.

Webber had a profitable morning, working through an aero programme as well as trying out the 2009 slick tyres. However, an unscheduled engine change cut short his afternoon programme.

Coulthard concentrated on evaluating the 2008 electronics and had a good day: "We made a lot of progress and it was very encouraging," said Chief Test Engineer, Ian Morgan. As planned, Coulthard is the only Red Bull driver running tomorrow.

Toyota welcomed Jarno Trulli back into action at today, where he joined Timo Glock. The Italian resumed the programme Kobayashi started, focusing on developing the new rear end and working with the 2008 standard ECU for the first time. The team's strong reliability record in testing means it is approaching the final day with the 30,000km annual limit getting close so Glock's programme was always scheduled to be shorter than his teammate's.

A hydraulic problem in the morning gave Glock an unscheduled break but he had the chance to test slicks in the afternoon, as well as continuing his set-up work. A string of red flags late in the afternoon disrupted proceedings but both drivers will return tomorrow to bring the curtain down on 2007.

"It was a positive day," said Trulli, "and it was good to be back in the car. We ran through all our planned programme running with the 2008 ECU and rear end of the car. This was the first time I have driven with the 2008 standard ECU but of course I have a lot of experience of driving without traction control. The main task was to put in a lot of mileage which have successfully done today. We concentrated on finding new things with the set-up and improving the general ECU settings. All in all it was quite a good day."

"Again we completed a lot of work today," added Pascal Vasselon, "although Timo did suffer a delay in the morning while a hydraulic issue was repaired. It was really interesting to run the slick tyres on Timo's car and we got a lot of information which will help us to adjust to the change in 2009. The difference between slicks and the current grooved tyres is quite big and the car behaves differently. Obviously there is more grip without the grooves and lap times are faster, which we expected, but it was interesting to note that the car balance and handling stays good with the slick tyres when we thought there could be difficulties. Jarno put in a hard day's work and we have made more progress with the 2008 ECU so now we look forward to concluding the year's testing tomorrow."

For Renault, Nelson Piquet spent the morning tyre testing, comparing the 2007-spec tyres with prototype 2009 tyres. The team also worked on start procedures without traction control, and continue to optimise chassis set-ups without electronic driver aids. On the engine side, the Viry engineers pursued their programme of fine-tuning the mapping of the RS27 to run harmoniously with the standard ECU, looking at parameters such as idle speed and the operation of the rev limiter.

There were no major problems throughout the day, and Piquet completed a full programme. He covered a total of 90 laps, equating to nearly 400 km, and set the seventh-fastest time.