Timo Glock believes a bigger budget is key for Marussia if the team is to make a significant step forward in the Formula 1 field.
Marussia made its grand prix debut as Virgin in 2010 and finished last in the standings in its first two seasons before moving up to 11th in 2012.
The team looked set to finish ahead of Caterham for the vital 10th spot, but it lost out in the final race of the season in Brazil, where Vitaly Petrov gave Caterham in best F1 result with 11th place.
Glock, who will stay on for a fourth season with the team, is aware that only with more money will Marussia be able to escape the back of the grid.
"More budget, that's the key point," Glock told AUTOSPORT. "We all know that if you want to make a big step, you need more money to do it.
"We develop in terms of our possibilities, but everyone else develops and they can develop faster with more money. Our main goal is to have more budget, that's what the guys are working on, and then we can make a step."
Glock reckons his team has been hurt by the lack of development in the windtunnel, having used CFD exclusively during its first two seasons.
This year's car made its track debut in the final test of the pre-season, and the team ran without KERS all year, unlike rival Caterham.
"I'm pretty sure we would have looked much stronger with proper testing at the beginning of the year and if we had started earlier in the windtunnel," he said.
"KERS too, but mainly if we had been able to shift everything with the windtunnel a bit earlier, we could have been closer to Caterham and maybe even beat them.
"That's where we're working for next year."