Sauber technical director James Key says the team is working hard to prolong its strong form following Kamui Kobayashi's drive to seventh place at Valencia.
The team under-performed in the early part of the season, but Key is determined to extend its run of good results with update packages planned for the next two races.
"We are in a position now where the car is more suited to some track layouts than to others," Key said. "Valencia showed that the car works when it's in the right conditions. Silverstone should be better suited to our car - it's mainly a mix of medium and high-speed corners, which our car is definitely well balanced for. Hockenheim might be a little less suited to our car than Silverstone.
"For Silverstone we have some front wing updates and modifications around the middle of the car. Then for Hockenheim we will have a rear end update which includes a diffuser step as well. The numbers in the wind tunnel are progressing well."
Key says the team is also working on low downforce performance for Spa and Monza, as well as dedicated a significant portion of its resources to next season's C30.
"We are a private team and we don't have unlimited resources to do everything we want," he said. "We are currently in the process of splitting our resources as best we can between the current car and the C30. We are focusing on Spa and Monza for lower downforce and drag configurations - and there will be further steps towards the end of the year."