An F-duct system will not be seen on Renault's 2010 car until the Belgian grand prix late next month.
No Renault F-duct in Germany
Robert Kubica said he is worried about Hockenheim this weekend, because the absence of the downforce-stalling concept means Renault is having to run less rear wing to keep up with the other cars.
"This could cost us in the corners," said the Pole.
Team boss Eric Boullier admitted recently it is "very likely" the system will not be seen at a grand prix until after the back-to-back events in Germany and Hungary.
The authoritative Auto Hebdo publication now confirms the news, revealing that Renault's F-duct will only be ready after the August break.