Formula One testing continues in Valencia, where Fernando Alonso put the new Ferrari F150 at the top of the time sheets on Day 2.
With each team allowed to run just one car at the test, the Spaniard is the only driver to have completed two full days of running. Team-mate Felipe Massa is set to have his first official laps in the car on Day 3.
Alonso has completed over 200 laps across the first two days, and emphasised the importance of getting comfortable with the new driver-operated moveable rear wing and KERS devices.
“It was a good start for us,” said Alonso.
“Today we did more than 100 laps, which was the priority – to do a lot of kilometres.
“The moveable rear wing has been a new device for us so we are making use of the system.
“It's not so easy to activate and de-activate before the corner, so there is some time of practice before we get used to it… and again the same with the KERS.
“So these extra buttons on the steering wheel require some time.
“I had some time in the simulator and now this time today, so I can say I am quite happy with everything in the steering wheel.”
Sebastian Vettel set the second fastest time for Red Bull Racing, completing 43 laps after Mark Webber had his first 17 laps in the car in the morning.
It was the Australian's first taste of the Pirelli tyres, having sat out the 2010 Abu Dhabi test and the opening day in Valencia.
The interim cars of Force India and McLaren were third and fourth fastest, while rival teams grappled with issues on their new cars.
For the second day in a row, Nico Rosberg's running was hampered by a variety of glitches.
“All of the main systems like KERS and the main wing often were not working or we did not have them on, and that then has a big impact on lap time,” explained the German, who was sixth fastest.
Sauber's Sergio Perez was left to lament rear bodywork and drive-train issues that limited his running to 42 laps.
The Mexican was less than a tenth faster than fellow rookie Pastor Maldonado, who had his first test of the Williams FW33.
Virgin Racing repeated its 2010 battle with hydraulics, while Heikki Kovalainen had an exciting 15 laps in the new Lotus.
“I wanted to give it more of a go but the power steering was failing inconsistently in different corners so it knocked some confidence away to have it jamming,” said the Finnish driver.
Several drivers noted extremely high tyre-wear with the new Pirellis, with Lotus Renault pilot Robert Kubica joking that the tyres will be ok “if you want to have a five or six-stop race.”
See below for the fastest times from Day 2