Valtteri Bottas says Williams knows it will be "much higher" in the standings on Saturday following an uncompetitive Friday in Belgium.
Both Williams drivers were comfortably outside the top ten during FP2 for the Belgian Grand Prix as Mercedes topped the times with Red Bull leading the rest of the field. However, Bottas says a simple change to the power unit on Saturday will deliver a clear step forward for Williams.
"I think it was definitely better than Hungary for us," Bottas said. "We were renewing today our test plan, and here especially when you turn up the engine it makes a big difference so, we know we can be much higher in the timesheets tomorrow. But today we’re just really trying different rear wing levels and getting information from the tyres."
And Bottas says he fully expects to be able to challenge Ferrari and Red Bull for the podium this weekend.
"We’re still trying different things [with tyres] between every run and I’m sure we’ll get the best config in the car with the options. There’s more to come.
"I think we can be close to [Red Bull and Ferrari]. They are definitely looking strong but I think we can improve quite a lot for tomorrow."
Click here for a gallery of the biggest crashes at Spa-Francorchamps
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