World Series by Renault champion Giedo van der Garde has admitted to being impressed by what he found when he tested with the French marque's Formula One team as reward for taking this year's title.

The Dutchman - who already has F1 experience from time spent with the Spyker and Super Aguri teams in 2007 - spent two days with the Renault team as the first test of the winter kicked off in Barcelona, and completed more than 60 laps in the 2008-spec R28 that Fernando Alonso took to two wins late in the season.

Having had a seat fitting at Enstone in the week leading up to the test, van der Garde joined race regular Nelson Piquet to begin the team's preparations for 2009, when the F1 rulebook demands a raft of changes, not least to the aerodynamics. Using Monday morning to observe the team's working methods, the former karting champion familiarised himself with the car during early afternoon runs over five laps, before being given longer outings on Tuesday morning.

It wasn't necessarily easy fitting the Dutchman into a car designed around the shorter Alonso and Piquet, but chief testing engineer Christian Silk confirmed that it had been a useful day for both parties.

"It's always special for us working with a new driver for the first time," Silk admitted, "We did everything we could to make Giedo feel at ease in the team and in the car - and that wasn't easy as he is pretty tall!

"We worked well together and he had the time to get used to the way we do things. The car is not like anything Giedo will have driven before, but spreading the session over two days meant he had a night to take in everything he learned from working with the engineers on the first day, and he improved constantly and worked very well."

Although he is expected to head to the GP2 Series next season - and is already getting experience there in testing and the Asia Series with iSport - van der Garde confirmed that the opportunity to join Renault had been invaluable.

"Everything about the F1 car is impressive - the acceleration, the cornering speed, the brakes...," he enthused, "On Monday morning , I watched Nelson and the technical team going about their work, and that set me up well for driving the car myself.

"I set off on some five-lap runs and constantly built up my speed. I'm used to driving with a very progressive accelerator, being gentle with the pedal, but the R28's accelerator suits the style of the team's drivers. You have to be quite aggressive with it and it's not easy to hold back.

"Towards the end of the morning, I had the chance to do a couple of new tyres runs, which helped me build confidence in the car and, each time, I improved my lap times. We made good progress across the two half-days and the team was happy with how things went so, overall, it has been a very positive experience."

Unsurprisingly, re-acquainting himself with an F1 car only whetted van der Garde's appetite for more, and the Dutchman may now attempt to find a testing deal to complement his racing activities in 2009.

"This experience has made me even more determined to get back behind the wheel of an F1 car some time soon," he noted, "Not only was the car a great drive, it was also a valuable experience working with the ING Renault F1 team.

"Their methods are generally reasonably similar to what I'm used to in the Renault series, but everything is that little bit more advanced - including the technology. The number of people who work on the car is staggering!"