Early on in the four-hour morning session, .
Team newcomer was second in the sister #8 car with a 1m29.719s, which he set with some 30 minutes remaining.
Rebellion improved on its best time from Tuesday by almost a second, as posted 1m30.110s in the second hour in the #3 Rebellion R-13.
That was just 0.487s shy of Conway's benchmark, with a further three tenths down in the #1 car.
Ginetta factory squad Team LNT also found significant time around the Circuit de Barcelona-Catalunya. in the #6 car.
In LMP2, another F2 frontrunner, , handed Racing Team Nederland the top spot in the TDS-run #29 Oreca 07.
The Dutchman posted a 1m32.941s, beating kept the #37 Jackie Chan DC Racing Oreca in the top-three, another three tenths back.
Ferrari continued to lead the way in GTE Pro as gradually worked his way down to a 1m43.593s in the #71 AF Corse Ferrari 488 GTE.
’s 1m43.945s effort.
Team Project 1 stayed ahead of the field in GTE Am, as led the way with a 1m44.467s in the #57 2018-spec Porsche 911 RSR.
Cairoli also set the second-best time in the #56 sister car, while made it a Porsche 1-2-3 with the #86 Gulf Racing car, staying within half a second of the lead.
The session was interrupted for 12 minutes after an early off for the #47 Cetilar Dallara LMP2 exiting Turn 4, which brought out the red flag.