Jenson Button concedes McLaren yet to get a complete handle on their MP4-28 car
Jenson admits 'at times the car feels good, at other times it doesn't'
By James Galloway in Barcelona
Last Updated: 21/02/13 10:50pm
The former World Champion returned to the Woking team's latest challenger for Day Three of the Barcelona test, a day on from team-mate Sergio Perez setting what still stands as the fastest time of the week on the soft tyres.
Button, however, experienced what he himself described as a "tricky" day in which he completed only 71 laps as McLaren spent the morning carrying out 'rake' work to understand the car's aerodynamics and general systems checks, before eventually switching to some longer runs in the afternoon.
McLaren have introduced a number of notable new concepts on the MP4-28, including pull-rod front suspension, and speaking to reporters at the end of the day, Button said he and the team were still getting to know the new car which explained its inconsistent performance level.
"It's been a very difficult few test days for me in terms of mileage," Button admitted.
"It's been very tricky to understand where the car is: at times the car feels good, at other times it doesn't. And a lot of that is basically understanding the car that we have and making sure it's working as we expect it to be working.
"Some of the time that hasn't been the case, so that's why it's been a tricky winter so far. But as you can see there are times when the car's working pretty well. Today on hards I did a 22.8 which I don't think is a bad lap with the fuel that we had on board, and obviously Checo [Perez] did a 21.8 on softs yesterday which is also a pretty good lap.
"At Jerez we showed pace, we also showed that we didn't have pace at other times. We don't know where we are and there's no point trying to compare ourselves to other people. We've got to sort out our own issues and get the best out of the car that we have."
Asked if he therefore thought the team were behind where they thought that would be after seven days of testing, Button replied: "In terms of laps completed and the testing that I have achieved, yes, I think we're behind on that. And a lot of it has been because we've been doing certain tests that have taken a bit longer than we wanted and as soon as one change takes longer it rolls into the next change and then it's lunchtime. So most of our testing is done in the afternoon these days!
"So it's not been perfect and we know we've got a lot of work to do in terms of spending more time out on the circuit and understanding the car."
McLaren's attempts to complete more mileage on the final day of the first Barcelona test appear likely to be hindered by rain on Friday and Button added: "It's going to be wet tomorrow so it is going to be tricky, and for me, I don't feel that I have had enough laps in the car and I think it is the same for Checo as well," he told Sky Sports News.
"I am really looking forward to a good test next week in Barcelona as I don't feel that we have been able to do enough to really understand the car and where we are with the car."
Despite ending the 2012 season with back-to-back wins in Austin and Brazil, McLaren's decision to introduce more revolutionary elements on the car relative to most of their rivals has been made in a bid to increase the development potential of the MP4-28.
Button acknowledged even an evolutionary version of the MP4-27 would probably have been quick come Melbourne, but insists McLaren will deride longer-term gains from their decision to change concepts for 2013.
"It's a very interesting season 2013, obviously with minimal regulation changes, because if we started this year with the [MP4-]27 - last year's car - with a few changes to it and developed that car through 2013, I think we could start with a very good car at the first race.
"Whether it would be better than the 28 I don't know but I think it would be a very strong car. But I think after two or three races you would realise you are at the end of the development curve. For us it was important to change the development of the car so we could see a new direction in terms of development throughout the year. And it's a long season - 19 races - it';s about being strong over the whole season and not just the first couple of races.
"I am still hoping we are competitive in Melbourne, it's a circuit I love and we have been competitive before the last few years. So I hope we're strong there, but there's a possibility that teams that kept the same car as last year and just developed it could also be strong."
The 33-year-old did, however, stress that he didn't currently see one car that looked clearly ahead of the field.
"Different cars are quick at different times and it depends on what tyre you use, and how much fuel you use. I don't think there is one standout team, or two standout teams, at the moment," he added.
"There might be at the first race but at the moment there's no one that stands out to me in being superior."