Marcel Fassler led an Audi 1-2 in opening Free Practice for Saturday’s FIA WEC Six Hours of Circuit of The Americas.
The No. 2 Audi R18 e-tron quattro reeled off a quick lap of 1:51.136 in the 90-minute session, edging out the sister No. 1 Audi of Tom Kristensen by 0.187 seconds.
Kristensen’s 1:51.323 lap was set late in the session, which saw overcast and cooler conditions, with a threat of rain.
The No. 20 Porsche 919 Hybrid of Brendon Hartley was third after leading the session early, with the pair of Toyota TS040 Hybrids completing the top-five overall and in LMP1-H.
The only noteworthy incident came late when the No. 8 Toyota of Anthony Davidson stopped on-track near pit out.
The No. 12 Rebellion R-One Toyota paced the LMP1-L class, although more than six seconds off the pace from the pace-setting Audis.
Extreme Speed Motorsports, meanwhile, topped the time charts in LMP2 in the team’s FIA WEC debut.
Ryan Dalziel pedaled the No. 30 HPD ARX-03b to quick lap of 1:58.111, outpacing the the No. 26 G-Drive Racing Ligier JS P2 Nissan of Olivier Pla by more than one-second.
The No. 47 KCMG Oreca 03 Nissan was third quickest in class.
Darren Turner led the way in GTE-Pro for Aston Martin Racing, turning a 2:06.399 lap time late in the session.
Turner edged out the No. 51 AF Corse Ferrari F458 Italia of Toni Vilander by more than four-tenths, with the pair of Porsche Team Manthey entries ending up third and fourth, respectively.
The No. 65 Corvette Racing C7.R, featuring brothers Ricky and Jordan Taylor and Tommy Milner, completed the top-five in class.
Aston Martin Racing, meanwhile, led the way in GTE-Am, thanks to Richie Stanaway’s 2:06.427, a time which put the New Zealander second quickest among the GTE contenders.
A second Free Practice is on tap for 7:30 p.m. local.
RESULTS: Free Practice 1