Tom McCullough believes Sauber's late upsurge will not have a negative impact on their 2014 Championship.
Despite having a dismal first half to this season, Sauber fought back in the second to end seventh in the Championship on 57 points.
It was an impressive turnaround and came at a time when rivals were switching their focus to next year and the many new regulations.
However, McCullough, the team's head of trackside engineering, insists Sauber still paid attention to 2014 and won't be left behind.
"To be honest, we haven't changed a lot on the car [late in the season]," he told Autosport. "We had one big update package.
"We started the work on the 2014 car, CFD and aero work, a long time ago.
"Yes, we had to do a little bit more on the 2013 car than we wanted to but there has been a team working very hard on that and a lot of the lessons we have learned with sorting out this car will apply to next year's car as well.
"From the resources we are playing with, we have been lucky not to have to put too much focus on this year's car."
McCullough added that Sauber's improved form was down to little adjustments rather than major overhauls.
"We still look at ourselves and think we didn't do a good enough job at the beginning of the year, that's clear.
"But we understood what the main problems were and focused our resource to improve those and we saw those gains coming.
"A lot of stuff was very right but there were a few small things that weren't.
"The track engineers and drivers just iterated away, understanding and improving, and we ended up getting a car into Q3 since Monza and had a car that deserved to score points every race."