( CNN ) -- Mark Webber endured a frustrating first test outing in the new Red Bull on Wednesday as his world champion teammate Sebastian Vettel was again near the top of the Formula One timesheets in Spain . Vettel finished top in Tuesday 's opening session of 2011 after completing 93 laps in Valencia , and the German was second-best behind Ferrari 's Fernando Alonso following another 44 laps at the wheel of the RB7 . Webber , however , was back in a lowly 14th after being able to drive just 17 laps of the circuit . `` I did n't get so long in the car today , so we will start the real work tomorrow , '' the Australian , who finished third overall in the drivers ' championship , told the official F1 website . `` There was a bit of a problem with the installation , something with the pedals , so it took a bit longer than we expected . It was n't the smoothest day , but we 're back tomorrow -- it 's great that the guys have got the car here for the first test and I 'm looking forward to driving it more . '' Red Bull unveil 2011 car ahead of title defense . Last year 's runner-up Alonso clocked a best time of one minute 13.307 seconds in his 108 laps at the wheel of the new F150 , to be the fastest of 15 drivers among the 12 teams taking part . The two-time world champion Spaniard was fifth after 98 laps on Tuesday . Force India rookie Paul di Resta was third after completing a day's-best 111 laps in the team 's 2010 vehicle , while fellow British driver Lewis Hamilton debuted for 2011 also in an old car as he was fourth for McLaren . `` It felt great to be back in the car . I have n't been driving for a while , so it felt good to brush away the cobwebs , and I felt at home straight away , '' the 2008 world champion said . `` We were trying to replicate 2011 downforce levels on the old car -- so it was n't 100 % accurate -- but we still got a good understanding of the new Pirellis and covered quite a lot of ground . `` The new tires are easy to get a feel for . There 's not as much grip as we had last year -- they drop off quite a bit , too , and they 're a little bit harder to control over a longer stint -- but it 's the same for everybody . '' Renault , Sauber and Lotus launch new cars . Hamilton 's McLaren teammate Jenson Button will also drive the modified MP4-25 in Thursday 's final session ahead of the launch of the new car on Friday and next week 's tests in Jerez . In fifth place , Lotus Renault 's Robert Kubica was the third driver to break 100 laps in the new R31 as he headed off HRT 's Narain Karthikeyan in the Spanish team 's 2010 vehicle . Nico Rosberg was seventh after 69 laps in Mercedes ' new MGP W02 as the German team bounced back from Michael Schumacher 's hydraulic problems on Tuesday . Williams ' Venezuelan rookie Pastor Maldonado was 11th after completing 29 laps in the afternoon in the new FW33 , with his veteran Brazilian teammate Rubens Barrichello ninth following his 50 laps . Sauber 's Mexican rookie Sergio Perez was 10th but could manage only 42 laps in the C30 before suffering serious power-train problems . Bottom of the field was Heikki Kovalainen in Team Lotus ' new T128 , which lasted only 15 laps in its track debut before a power-steering fault ended the Finn 's session .
Ferrari 's Fernando Alonso fastest in the second day of F1 testing for 2011 . The Spaniard was quickest on Friday and Saturday, but he has been unable to match his team-mate Sebastian Vettel this week as they have struggled with engine problems during their first two days at Silverstone. But German 's teammate Mark Webber 's session ends after only 17 laps . Lewis Hamilton is fourth ahead of the launch of the new McLaren on Friday .