Renault is a more open team to work with than was BMW-Sauber, Nick Heidfeld has admitted.
The German, who has replaced the injured Robert Kubica this year, was paired with the Pole for several years at BMW-Sauber before the carmaker pulled out in 2009.
"Renault is extremely open," the 33-year-old, referring to the Lotus-sponsored team owned by Genii Capital, said in an interview with Frankfurter Allgemeine Zeitung.
"My ideas and constructive criticism are welcome," added Heidfeld. "I've never seen that quite so much as with this team.
"Of course not everything is adopted, but there is that dialogue. And that's a lot of fun. The (2011) car was obviously ready when I came, but I was able to bring something in many areas."
Of course not everything is adopted, but there is that dialogue
He revealed that some teams are open while "some are closed", and admitted that BMW - the Hinwil based team once again now known as Sauber following BMW's withdrawal - is in the latter category.
"They were very, very well organised," said Heidfeld, "but I think sometimes too narrow. They would not venture from the plan even one step to the right or left," he added.