Coulthard believes the engine partnership with Honda will see the team pushing for race victories in the season ahead.
He said: "They have to, as a company that have produced world championship engines and have turbo technology from Indycars, be at least where Renault and Ferrari are. They can't be worse than that, in my mind's eye.
"And where Renault were last year was good enough to win three grands prix.
"Of course they won't be pitching themselves as championship contenders in 2015 but why would you not pitch for race victories if Red Bull can finish second (overall) with a Renault (engine) that clearly was struggling?"
Coulthard, who drove for McLaren for nine seasons, believes McLaren can close the gap on pack leaders Mercedes in the coming season.
He added: "I think the goal has to be to try and win a grand prix in 2015, not just try and get a podium. Mercedes will probably still be dominant but Red Bull, Ferrari and those teams must be closer and McLaren-Honda have to be in amongst that mix."
He also talked about driver Fernando Alonso's switch from Ferrari to McLaren, saying: "Fernando has still got to be regarded as the drivers' driver. It's a marriage of convenience rather than pure love – the cuddly pictures don't fool anyone do they? – but Alonso is a serial winner and McLaren have been."