Max Verstappen said he was "smiling" after testing his new Red Bull at Silverstone on Wednesday as he plots a way to dethrone world champion Lewis Hamilton.
The Dutchman, who joined the Mercedes driver on the track, is tipped to be among Hamilton's chief challengers this year.
'Very happy with how the car was behaving'
Red Bull unleashed a special-edition livery with the revamped paint job featuring substantially more red, but it is understood the former world champions will revert to their normal colours in time for the season-opening race in Melbourne on March 17.
"The day's done, first few kilometres with the car," Verstappen said in a video on the Red Bull Racing Twitter account.
"After my first run I was smiling, very happy with how the car was behaving plus the engine as well. Very positive. Really nice group of people to work with as well so I just can't wait to get started now for Barcelona and start working towards Melbourne. It was a very positive day so very happy about it."
The 21-year-old's hopes of a title charge will be determined by the performance and reliability of his team's new engine partner Honda.
Red Bull will be powered by the Japanese manufacturer this year after ending their fractious relationship with Renault.
Australian Daniel Ricciardo has left Red Bull to join Renault with Verstappen, who finished fourth in the drivers' standings last year, to be partnered by young Frenchman Pierre Gasly.
"I am very excited to get started as the off-season has been quite long," Verstappen said earlier. "The first two or three weeks feel like they are good to have and then after a break you want to get going.
"We are expecting a lot from Honda and are positive, but it will not be perfect from race one. I am optimistic, but also realistic and only time will tell as to how we will get on.
"I want to get the best out of myself, but you have to see what the car and engine are going to do.
"Until we get to Australia, my goals are a bit blind. In Formula 1, it is so related to the package so at this stage I am quite easy going."
Verstappen will get the first proper taste of his new Red Bull during next week's first pre-season test at Barcelona's Circuit de Catalunya.