The Brazilian made his debut with the Swiss team this year, and with his backing by the Banco do Brasil he will stay at Sauber in 2016.
But Nasr, 23, told O Estado de S.Paulo newspaper: “I will not win a race with the Sauber car, and I think many people understand that.
“Of course I want to be in a better situation, fighting for wins and podiums in a more competitive team.”
Nonetheless, Nasr said he is happy with how his first season on the grid has gone, insisting that despite recurring brake problems he gained “a lot of experience”.
“The highlights were fifth in Australia and sixth in Russia, showing that when there were opportunities I was there to grab them.
“I think that’s what people want to see. Knowing the limitations of Sauber, I could show why I came to formula one,” he added.
Asked what lessons he learned from 2015, Nasr continued: “I think I learned to control my frustrations. We started the year very well but then had a lot of trouble due to a lack of car development.”
As for how 2016 might go, he answered: “It’s difficult to know what to expect.
“The concept of the car is quite different. What we have this year is very similar to 2014, with very few updates. Next year is very different with a more aggressive concept. And everyone is expecting an improvement,” said Nasr.