Force India drivers Nico Hulkenberg and Sergio Perez say that the squad has made immediate progress following the introduction of a B-spec car during practice for the British Grand Prix.
The VJM08 used at Silverstone featured modified bodywork, the most striking being 'nostrils' carved into the nose section of the car.
Hulkenberg was able to set the eighth fastest time during the second practice session, with Perez in 13th place.
"It was a smooth Friday, with no dramas, and overall a pretty positive day," said Hulkenberg.
"When you get a new package, that’s just what you need and we were able to complete good mileage. We found performance straight away: from the very first run I had a positive feeling and that's an encouraging sign.
"With new parts on the car, there is always a steep learning curve, so we will need to pore over the data tonight to find some more margins to optimise, but I am really optimistic."
Perez added, "I think we can be happy with what has been a very positive start with the B-spec car."
"We got good mileage today so there is plenty to analyse and learn, but I feel we have definitely taken a step forward, which is what this team was expecting. It is always a complex task to learn about all the new parts in just a couple of sessions, but by the last run of the session, I was feeling comfortable, and that’s promising for the race."