Rubens Barrichello has admitted there will be no quick solution to Williams' current lack of pace.
No quick fix for Williams
The newly Cosworth-powered FW32 showed signs of promise in the pre-season, but has collected just 6 points from the first four races, causing technical boss Sam Michael to surmise that the car is "not fast enough".
"We know exactly some of the areas in which we need to improve," said Barrichello, who joined Williams from F1's title winning team of 2009, Brawn.
"We are not suddenly going to find a second (per lap) from somewhere, but the important thing is that I am firmly convinced that the second is in the car," he is quoted as saying by Speedweek.
"We want to be in the top six in qualifying, but even to achieve this, we need to find half a second," added the Brazilian veteran.
On the positive side, the 37-year-old said that he and Williams - just his fifth team in 18 consecutive seasons in F1 - are already working well together.
"There is a good harmony between driver and team," he is quoted as saying by Brazil's Globo.
"The best thing is that I am not happy with the results and neither is the team. We just need to keep on working.
"Williams are prepared to listen to me, which is good. They really trust my inputs so I am feeling good about that," added Barrichello.
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