The Formula Regional European champion, who is testing for ART Grand Prix, set a 1m21.300s on Wednesday morning, the quickest time of the three-day test.
The Swiss driver has admitted the step up to F3 had so far proven “easier than I was thinking”, having stepped into new machinery less than 24 hours after taking his title at Monza on Sunday.
Caio Collet was second quickest on Wednesday, remaining with MP Motorsport, having finished ninth in 2021, with Roman Stanek in third, testing for Trident.
This year’s runner-up Jack Doohan was fourth quickest, setting a 1m21.437s for newcomers Van Amersfoort Racing. He also topped the afternoon session, with a 1m22.354s.
Reece Ushijima was second quickest in the afternoon, making the step up from the GB3 Championship, with Jonny Edgar in third, testing for Trident having finished 18th for Carlin in 2021.
There were seven changes for the final day of testing, with Victor Martins returning to the ART Grand Prix cockpit in place of Juan Manuel Correa.
Alex Smolyar and Filip Ugran replaced Rafael Villagomez and Reece Ushijima at Van Amersfoort Racing, with Ushijima switching to Campos Racing in place of David Vidales.
Brad Benavides tested for Carlin instead of Ido Cohen, who moved to Jenzer Motorsport on Day 3. The Israeli will replace Nazim Azman, who spent the day at Charouz Racing System, instead of Ugran.
Doohan topped the timesheets for Van Amersfoort Racing on the first day of testing, setting a 1m22.402s in the afternoon session following a wet morning running.
He led from ART Grand Prix pair Saucy and 2021 runner-up Victor Martins.
Jak Crawford led Day 2 for Prema, setting a 1m21.368s ahead of ART Grand Prix’s Gregoire Saucy and Trident’s Roman Stanek.