Jenson Button says his Honda team still have a lot of work to do if they are to compete at the front of the grid when the 2007 season starts on 18 March.
Honda hope their new-look car will raise awareness on climate change
The new RA107 car, which was unveiled on Monday sporting a new livery promoting environmental concerns, has disappointed in testing.
"We still have another test in Bahrain with a lot of things to test," he said.
"Hopefully they will help because we are not on the same pace as the Ferraris, the McLarens or the BMWs."
The 27-year-old added: "We've improved a lot but still we're not where we want to be.
"We're not quite there but all we can do is get our heads down and hopefully improve the car as soon as possible.
"We are definitely going in the right direction."
Honda unveiled their car's livery for the 2007 season on Monday and have chosen to scrap advertising and feature an image of the earth.
The RA107 car, driven by Button and Rubens Barrichello, will aim to raise awareness of climate change.
Team boss Nick Fry said: "We believe Formula One can play an important role in highlighting the issue and play our part in developing solutions."
Honda have been testing over the winter in a plain black car and will complete their final sessions in Bahrain this week.