Toyota's Timo Glock ended a week of Formula One testing in Jerez, Spain, Wednesday with his team's best showing -- top time -- as scattered rain showers interrupted runs and disrupted all teams' test schedules through most of the day.
With the exception of Scuderia Toro Rosso, whose Sebastian Vettel went off to end his day's testing, and McLaren, whose Lewis Hamilton was credited with two off-track excursions, teams were not forthcoming about who went off or how many times as drivers continued to adapt to cars in the wet without traction control. Red flags stopped testing several times before the track dried completely in late afternoon.
The only driver to get under the 1-minute, 20-second mark, Glock posted a 1:19.779 in 96 laps in the TF108/02. He was followed by Hamilton in the McLaren Mercedes MP4-23 at 1:20.099 in 73 laps, then Fernando Alonso driving last year's Renault, an R27-06, to 1:20.363 in 49 laps.
"I am pleased with our progress today, and I believe we have made some significant improvements to the new car," Glock said. "It is encouraging to see us end the day with the fastest lap, and I think we made a step forward. Once again the car was extremely reliable and that allowed us to complete a lot of laps and gather plenty of information."
His quick time giving reason for early hope for a turnaround in the misfortunes of the high-dollar, low-reward Japanese team, yet to bag a victory in five seasons, Glock said the TF108 is "a completely different car" to the TF107 and conceded he spun in the morning after making a mistake, allowing that the off didn't cost much time.
"The team worked really hard this week to improve the car, and I am happy," he said.
Rookie Sebastien Bourdais drove to fourth-quickest, 1:20.407, in the Toro Rosso STR2-02. His teammate, Vettel, clocked slow time of the day, a 1:24.873, in 50 laps.
Ferrari's Felipe Massa managed a 1:20.500 in the F2008 followed by McLaren's Heikki Kovalainen (MP4-23) in 1:20.535, Toyota's Kamui Kobayashi (TF107/06) in 1:20.577, Ferrari's Kimi Raikkonen (F2008) in 1:20.646, and Kazuki Nakajima (FW29B) in 1:20.758.
Red Bull's David Coulthard took the first laps on the new RB4, unveiled earlier in the day. Although he was near the bottom of the unofficial times sheet, at 1:22.581 in 54 laps, car designer Adrian Newey indicated putting the car on-track was progress.
"Today was all about giving the new car a good shakedown and getting some miles on it," Newey said. "Now we hope to settle down to proper performance testing, starting in Valencia next week. The car's potential? Far too early to say."
Red Bull driver Mark Webber voiced an interest in reliability for the 2008 season, telling BBC Sport, "This year the car should be a damn sight better than last year, but then it's not hard to improve on what we did last year." He and Coulthard missed finishing nearly a third of last season's races owing to breakdowns. Webber drove an RB3 to a 1:22.275 in 53 laps.
Williams test drive Nico Hulkenberg posted a 1:24.023 in 65 laps.
Accumulating 71 laps, Force India's Adrian Sutil worked on electronic control unit, set-up and fuel cell evaluations. The German's best lap time, 1:21.705, was recorded on a track damp throughout the afternoon.
"With the rain it was not the best conditions at the start but at least this morning we did a lot of running in the wet, which was helpful as we tried some different settings," Sutil said. "We still have quite a lot of work to do, but in the end I was quite happy."
Missing from earlier in the week when a breakdown forced them to send out for spare parts, Super Aguri were not on track.
At Valencia, Spain, where BMW Sauber continued its private test at the 4.005-kilometer (2.488-mile) Ricardo Tormo circuit, strong winds hampered Robert Kubica at the wheel of in the F1.08-02. No useful data were gathered although the Polish racer completed 105 laps. The team instead focused on long runs to do system checks. In the F1.07-06, Nick Heidfeld completed 74 laps and practiced starts. Estonian test driver Marko Asmer is scheduled to drive the F1.07B Thursday, when Heidfeld will drive the F1.08.