Among the teams running are the German, British and Italian BMW teams, SEAT Sport and Ford Hotfiel Sport, and the test follows on from one held at Silverstone on March 1-3. No times were released, but SEAT driver Rickard Rydell was fastest over the three days
Thirteen cars are currently testing at Magny Cours ahead of the opening rounds of the series, to be run at Monza on April 10.
"I was impressed how the Toledo behaved on this track," Rydell noted. "I hope my experience here from my BTCC years, and the work we've done, is useful when we come back here to race."
BMW Team UK's Andy Priaulx was equally impressed with his team's performance, stating: "The car felt very good, and the new updates definitely seemed to have made a difference. However, the most surprising thing of all was the weather.
"We were in the UK in March and we had three dry, relatively warm days. Someone was looking after us - if we had been there the week before we would have been waiting for the snow to melt!"
Entry into the series is now closed, with 25 cars representing seven different manufacturers entering for the full season. A number of other cars will take part on a race by race basis, with grids expanding up to 32 cars at some events.
Five manufacturers - Alfa Romeo, BMW, Chevrolet, Ford and SEAT - have entered into the Manufacturers' Championship.
The current test is expected to finish tomorrow (March 17), although it is unlikely that times will be released. From there the teams will move to Monza for a media launch on March 22, ahead of an open day for fans in Milan on April 7.
On that day an exhibition featuring cars from all manufacturers will be held in the Plaza del Duomo in the heart of Milan, and a number of drivers will attend between 2 and 6pm to meet the public ahead of the first two races in the series, at Monza.
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