Charles Pic believes that Caterham's Renault engine and KERS is its biggest advantage over rival team Marussia.
The Frenchman has switched from Marussia to Caterham this year, giving him a direct comparison of the two teams that fought over 10th place in the constructors' championship last year.
When asked how the Caterham CT03 compared to the Marussia he raced last year, Pic told reporters at Jerez: "The biggest difference is coming from the engine side and the KERS.
"Last year [at Marussia] we didn't have KERS, and yeah, it's quite different. It's a new part, but it's quite fun.
"You have to learn how to use it and where you decide to recover the energy, because it gives you extra rear braking which can cause [wheel] locking which disturbs the balance."
Pic added that he did not want to focus on comparisons between the two back-of-the-grid teams.
"I had a great year with Marussia and I'm very happy to be in Caterham for now and the future," he said. "I don't want to compare them.
"What was different was the engine and the KERS, of course. After that, I think they are two young teams who are working hard to progress.
"Of course there are some differences. We will see in Australia who is the best."
News editor Glenn Freeman
The things Charles Pic didn't say gave away almost as much as what he did say after his first test for Caterham on Thursday.
As the first driver to cross the divide between the two remaining 'new' teams, Pic has got a fascinating insight into the differences between them.
It's very diplomatic of him not to go into great detail, but he was given plenty of opportunities to at least suggest there was something other than the engine and KERS that is better on the Caterham.
True, he only has one day in his new car to his name and we're in the early stages of pre-season. But the fact that he didn't take any of those opportunities suggests that there is probably very little to choose between the two cars once you take the Renault vs Cosworth comparison out of the equation.
That was a theory that gathered pace as Marussia closed on Caterham towards the end of 2012, and perhaps Pic has given us the clearest indication yet of just how accurate it is.