US GP practice quotes: Williams

Valtteri Bottas - 3rd/16th: We did some aero testing with new parts for the car today, which look like they may provide some small gains. The track was quite slippery in the morning which seemed to suit our car but as the track improved in FP2 we struggled with the car balance. The performance in the first session showed our potential, so if we get everything right and the weather suits us it may be better for us tomorrow and Sunday

Pastor Maldonado - 10th/18th: It was a difficult session today, particularly trying to get the most out of the tyres. We are struggling to get the maximum downforce here and the car feels like it's not working together between the front and the rear. The circuit is very enjoyable to drive and fast through the corners; hopefully we can look at the data from today and put a package together for the weekend to suit our car.

Xevi Pujolar, Chief Race Engineer: We didn't get as much running as planned in FP1 due to the delayed start, but we still managed to complete most of our tests. Valtteri had a development floor which worked as expected whilst Pastor worked through a number of aerodynamic tests. Initial comments from the drivers were that the grip level was better than last year, but that they were still struggling to get the tyres to warm up. In FP2 both drivers did some further tests with different floors. Pastor also had a different exhaust configuration and rear wing level, but overall the grip and pace wasn't as good and he struggled to get the tyres to work. With the higher track temperatures we couldn't improve our times but we were happier with the configuration on Valtteri's car so both will run this tomorrow.