Heikki Kovalainen broke the Red Bull family grip on quicks Friday during the final day of Formula One testing at Jerez de la Frontera, Spain. The Finn drove the McLaren Mercedes MP4-23 to a fast lap of 1 minute, 18.385 seconds, best of a four-day test on the 2.84-mile circuit.
Kovalainen covered 83 laps using various aerodynamic attachments, incloding horn wings on the nose. He worked in southern Spain's typically warm summer conditions, track temps reaching 110 degrees Fahrenheit.
Scuderia Toro Rosso's Sebastien Bourdais, the defacto American in the series given his lengthy career in Champ Cars, followed Kovalainen under the 1:19 mark with a 1:18.746. The only other driver to dip below 1:19 during the week was Bourdais teammate Sebastian Vettel, fast runner the first two days who ran a 1:18.843 on slicks on the second day. Bourdais put in 113 laps in the STR3, mostly on slicks.
"The day went quite well," Bourdais said. "Running the '09 tyres was very interesting, even if a combination of a very abrasive track surface and a 50-degree track temperature meant they did not last very long. We have also come up with some useful data for Hungary and, to be honest, that's the most important thing about this test, as 2009 is still a long way away."
Shoring up the Red Bull week of formidable showings, including his teammate Mark Webber going quickest on Day 3, David Coulthard was third-fastest in a Red Bull RB4. He ran 1:19.494, ahead of Romain Grosjean in a Renault R28 at 1:19.561. Grosjean, looking to move into F1 from the GP2 feeder series, covered 90 laps and earned praise from chief test engineer Christian Silk.
"It was a good day with Romain, and he settled into the program quite quickly," Silk said. "He was giving good feedback to the engineers and showed consistency on the long runs this morning."
Felipe Massa concentrated on race setup for Hungary, site of the next race. The Brazilian ran fifth-best with a 1:19.611 His work included aerodynamic testing of a so-called shark-fin engine cover.
Kazuki Nakajima put the Williams FW30 sixth-quick at 1:19.724. He, too, concentrated on race setups for Hungary, racking up 100 laps in hot, humid conditions. Nakajima had the wheel for a second consecutive day after Nico Hulkenberg took Day 1 and Nico Rosberg Day 2.
"Over the four days, the team completed some extensive testing on the latest generation of Bridgestone slick tires, adding to the knowledge base required to optimize the cars for the new regulations in 2009," chief operations engineer Rod Nelson said. "Back on this year's grooved rubber, both drivers then did some work on systems and setups in preparation for next weekend's Hungarian Grand Prix, where we expect similar weather."
Nick Heidfeld ran seventh-best, 1:19.915. in a BMW Sauber F1.08. The German concentrated on race setup for Hungary, trying out aerodynamical and mechanical combinations. He brought out a red flag when he stopped during the morning session with a sensor failure.
Adrian Sutil made the most of Force India's new seamless shift gearbox with the final 1:19 lap, a 1:19.965. Force India chief race and test engineer Dominic Harlow said Sutil adapted well to the change. Force India skipped the first test day so worked a three-day test while the rest of the teams completed four days.
"We got off to a good start this morning with Adrian very quickly getting used to the seamless shift gearbox," Harlow said. "In the afternoon we again tested the 2009 development tires, allowing Adrian to get some more experience of driving on slicks. Overall, it's been a good test with more than 1,000 kilometers over the three days, and we feel well-prepared for Hungary."
Honda race driver Jenson Button stepped in for the final day's test and clocked up a 1:20.532 in the RA108. He covered 98 laps.
"We ran the car with our latest aero and suspension developments today to complete the evaluations which have been ongoing all week," Button said. "The new parts have made a small but tangible improvement to the stability of the car, which is particularly evident over longer runs, so it has been a positive day. It will be interesting to see how this translates over the race weekend in Hungary."
Head of Honda's race and test engineering Steve Clark said the team tested all aspects of the car: aerodynamics, engine, suspension, brakes and tires. The RA108 has undergone rear suspension upgrades he called "significant" and which benefit the aerodynamic performance. He said all three drivers testing this week, test and reserve driver Alex Wurz as well as race drivers Rubens Barrichello and Button, agreed that braking stability has improved.
"This is an issue which has previously prevented us from achieving a good balance on the car and, as well as being a gain for the remainder of this season, it will give us a strong direction for the 2009 car development," Clark said. "Also relevant to the 2009 car was the evaluation of the slick tires by Alex. Using both compounds, we gained an important insight into what will be need to best exploit the tires next year."
Test driver Kamui Kobayashi rounded out the time list in a Toyota TF108 with a 1:20.878.
"We spent most of the day working towards the race in Budapest next week," Kobayashi said, "and we made good progress. Late on, we switched our attention to Bridgestone's slick tires for 2009. The track obviously changes quite a lot during the day here, becoming more difficult for testing in the heat of the afternoon, but we weren't looking for lap times. We had a lot of different aero parts to try. We completed our program, and we collected some useful data."
On to Hungary.