Saucy, the 2021 Formula Regional European Champion, put his ART Grand Prix to the top of the timesheets with a 1m21.300s in the three-hour morning session.
The 21-year-old Swiss racer’s benchmark remained unbeaten in the final afternoon session as Saucy concluded the three-day test with the outright fastest time, 0.068s quicker than what Prema’s Jak Crawford managed on Tuesday.
With teams running out of fresh sets of Pirelli tyres, there was less track action than the previous two days at the Ricardo Tormo circuit.
Saucy hit the front in the opening hour and traded fastest times with MP Motorsport’s Caio Collet before he eventually regained top spot by less than a tenth.
Trident’s Roman Stank rounded out the morning times, the majority of which were not bettered in the afternoon running.
Morning top 10: Saucy, Collet, Stanek, Doohan, Colapinto, Maloney, Frederick, Crawford, Aron, Martins.
The lack of new tyres resulted in less action in the afternoon, but it was 2021 F3 runner-up Jack Doohan who eventually ended up fastest after Van Amersfoort Racing stablemate Filip Ugran saw his quickest time deleted for track limits.
Doohan completed just 29 laps in the afternoon compared to his morning haul of 64.
While Doohan’s 1m22.354s was over a second adrift of the best time set by Saucy in the morning, it was enough to ensure that F3 newcomers Van Amersfoort topped a total of three of the six track sessions at Valencia.
Reece Ushijima (Hitech GP) and Red Bull junior Jonny Edgar (Trident) separated the Van Amersfoort trio, with Alexander Smolyar and Ugran completing the top-five positions on Wednesday afternoon.
Afternoon top 10: Doohan, Ushijima, Edgar, Smolyar, Ugran, Collet, Yeany, O’Sullivan, Sargeant, Hadjar.