Di Grassi pleased with progress

While the Brazilian had some good results in the early races of the year, he openly admitted that he was not happy with his pace, but he now believes that he will be stronger in the remaining races.

Di Grassi took a second and a fourth place finish last weekend at Magny-Cours, and he is now 10 points behind championship leader Timo Glock, who retired from both races in France.

"The main thing that makes me really happy is that we improved the car a lot from the last race," said di Grassi. "The car was really good, really consistent.

"We had really good pace compared to everyone else, and for sure it was something that was missing from those races.

"The car was not good before, and I got two podiums but I was not happy. Now I'm much more happy."

However, the 22-year-old admitted that it was hard to judge just how much ART have improved their race performance at the weekend, as he did not have to race the iSport cars at any point.

"We need to see iSport's pace, because I really didn't see how quick they were," he added. "If it's the same gap as before then no difference.

"If we're closer then we improved, so I'll wait for Silverstone to see how their car really is, and then we'll see if there's an improvement."