Bouyed by a front row start at the previous round at Valencia, the German lapped the Le Mans Bugatti circuit in 1:41.109 to top the first group of qualifiers - which was faster than the later second session despite the drying track.
However, the rest of the grid placings are unknown because team officials have requested a change to the way the grid is to be determined, which race stewards are currently considering.
The World Series by Renault cars are split into two separate 15-minute qualifying sessions to limit the problem of traffic ruining hot laps. Victory Engineering's Enrico Toccacelo was fastest of the second batch of runners that ran after Winklehock's session.
Because Winkelhock posted a faster time than Toccacelo, the previous system would have meant the drivers in the German's session would start on the odd-numbered grid slots. The drivers in Toccacelo's slower session would have started behind him on the even numbered grid slots.
However team officials have requested that in cases where the average of the five fastest times within each session are within 0.3 per cent of the fastest time, then the grid would be determined on overall qualifying times regardless of in which session they were set.
If this system is used, then Valencia winner Tristan Gommendy would line up on the front row, having posted a faster time than Toccacelo in the earlier session.
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