The Williams team believe their victory in the Brazilian Grand Prix could prompt a renewed challenge next year.
Williams-BMW's Juan Pablo Montoya beat McLaren-Mercedes' Kimi Raikkonen to victory in Brazil, to finish a sometimes trying season on a high.
"I am proud of our recovery from a difficult situation and we have now come back to former strengths," said BMW motorsport director Mario Theissen.
"This was a great relief for the team after a long and tough season."
McLaren, who have signed Montoya to partner Raikkonen in arguably the sport's strongest driver pairing next season, also believe they can continue their momentum in 2005.
Team boss Ron Dennis said: "It's been a tough season but it shows the depth and strength of the entire team that we were able turn things around and challenge for victories.
"We now look forward to 2005 where we want to start the season in a strong position with Kimi and Juan Pablo.
Montoya's victory ended a long barren patch for Williams, who had not won since the German Grand Prix in August 2003.
The team, who started the season expecting to challenge for the title, finished fourth in the constructors' standings.
Technical director Sam Michael was full of praise for Montoya's performance in Brazil.
"What a fantastic way to finish the season, Juan Pablo had a superb drive and didn't put a foot wrong," Michael said.
"It's been a hard season for us and this is a great reward for everyone who has worked so hard," he said.
Williams will lose both their drivers next year, with Ralf Schumacher moving on to Toyota.
Only Mark Webber has been lined up for 2005, after Williams lost its legal battle with BAR for the services of Jenson Button.