Sergio Perez is confident that Sauber will return to form in this weekend's Japanese Grand Prix.
The Swiss team will run a major aerodynamic upgrade package for the first time during Friday practice. This will include new front and rear wings, turning vanes, sidepod deflectors and new brake ducts, as well as modifications to the floor.
Sauber has scored only three points in the last five races, slipping to seventh behind Force India in the constructors' championship, and Perez expects the car to be more competitive on his first visit to Suzuka.
"I'm very confident about this weekend," said the Mexican, who finished 10th in the Singapore Grand Prix two weeks ago. "We are bringing a big update here so hopefully it works and we can move ahead.
"Singapore was a very good weekend for Force India, so we want to score very big points here to try to catch them up."
Team-mate Kamui Kobayashi believes that, if the update works well, it will be a big step forward for Sauber.
The Japanese is chasing a return to form after scoring only two points in the last seven races.
"We have a reasonable update," said Kobayashi. "It will be the last big update for us. Aerodynamics are important at this circuit, so if it works well, we will see a clear result. That's what we want for this weekend."