Valtteri Bottas says Williams has yet to solve its wet weather problems after trying some set-up tests during practice for the United States Grand Prix.
Williams has struggled in the wet for the past two years, with the team often less competitive than it is rivals in the rain compared to dry conditions. Following a number of tests in Japan where Williams felt it was making progress with its set-up, Bottas says Friday's wet running in Austin showed it is still off the pace.
"We had one set of tyres to use up, anyway, in the first session, so we did some mechanical set-up tests, with both cars trying different things," Bottas said. "We managed to improve the balance of the car a little bit, but the main problem remains that we lack overall grip in the wet.
"We had quite heavy front tyre graining today – I don’t know if the other teams had the same issue – and that was quite a big problem for us. I just about managed to get myself into the top ten, but the gap to the quickest cars in the wet is still big, so we need to find some big improvements for the future."
With heavy rain threatening to have an impact on the time qualifying takes place, Bottas says he has no problems with qualifying on Sunday morning but hopes the weather favours Williams.
"I think it’s OK. We’ve been here a couple of times before, we know the braking points and the lines. If it’s like that, then we may have an interesting qualifying session, but it will be the same for everybody. The only thing we can hope for is that it’s dry, because that would be so much better for us."
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