Felix Serralles put European Formula 3 Championship newcomer West-Tec on top of the times as the second pre-season test began at Zeltweg on Tuesday.
The squad, which has graduated from British F3 and the former European F3 Open series, and its Puerto Rican driver set a best time of 1m25.244s in the afternoon session at the Austrian Grand Prix Formula 1 venue.
Antonio Giovinazzi continued his strong form from last week's Hungaroring test in second place for Carlin.
Morning pacesetter Riccardo Agostini of Eurointernational ended up third overall.
Title favourite Felix Rosenqvist was fourth ahead of Giovinazzi's team-mate Ed Jones.
Rookies Esteban Ocon and Max Verstappen were Agostini's closest challengers in the morning, slipping to seventh and eighth behind Nicholas Latifi in the combined standings.
Jordan King and Ferrari protege Antonio Fuoco completed the top 10.
Formula Renault 3.5 driver Marco Sorensen stood in for fellow Lotus F1 junior Oscar Tunjo at the Renault-powered Signature team. He was 25th overall.
Carlin's Tom Blomqvist had to sit out the opening day due to engine problems that had begun in Hungary last week. He will resume running on Wednesday.
Pos Driver Team/Car Time Gap 1. Felix Serralles West-Tec Dallara-Merc 1m25.244s 2. Antonio Giovinazzi Carlin Dallara-VW 1m25.328s +0.084s 3. Riccardo Agostini Eurointernational Dallara-Merc 1m25.617s +0.373s 4. Felix Rosenqvist Mucke Dallara-Merc 1m25.657s +0.413s 5. Ed Jones Carlin Dallara-VW 1m25.794s +0.550s 6. Nicholas Latifi Prema Dallara-Merc 1m25.847s +0.603s 7. Esteban Ocon Prema Dallara-Merc 1m25.851s +0.607s 8. Max Verstappen Van Amersfoort Dallara-VW 1m25.863s +0.619s 9. Jordan King Carlin Dallara-VW 1m25.956s +0.712s 10. Antonio Fuoco Prema Dallara-Merc 1m25.974s +0.730s 11. Sean Gelael Carlin Dallara-VW 1m26.073s +0.829s 12. Dennis van de Laar Prema Dallara-Merc 1m26.086s +0.842s 13. John Bryant-Meisner Fortec Dallara-Merc 1m26.125s +0.881s 14. Lucas Auer Mucke Dallara-Merc 1m26.150s +0.906s 15. Felipe Guimaraes Double R Dallara-Merc 1m26.280s +1.036s 16. Roy Nissany Mucke Dallara-Merc 1m26.320s +1.076s 17. Jake Dennis Carlin Dallara-VW 1m26.323s +1.079s 18. Mitchell Gilbert Fortec Dallara-Merc 1m26.439s +1.195s 19. Michele Beretta Eurointernational Dallara-Merc 1m26.505s +1.261s 20. Hector Hurst West-Tec Dallara-Merc 1m26.605s +1.361s 21. Sandro Zeller Jo Zeller Dallara-Merc 1m26.616s +1.372s 22. Spike Goddard T-Sport Dallara-Nissan 1m26.686s +1.442s 23. Alexander Toril T-Sport Dallara-Nissan 1m26.773s +1.529s 24. Gustavo Menezes Van Amersfoort Dallara-VW 1m26.781s +1.537s 25. Marco Sorensen Signature Dallara-Renault 1m27.321s +2.077s 26. Jules Szymkowiak Van Amersfoort Dallara-VW 1m27.511s +2.267s 27. Tatiana Calderon Signature Dallara-Renault 1m27.521s +2.277s