Joel Miller led a Mazda 1-2 sweep in opening IMSA WeatherTech SportsCar Championship practice for Sunday’s Continental Monterey Grand Prix.
Miller’s fastest lap of 1:18.564 was a scant 0.004 seconds off Johnannes van Overbeek’s record lap set at Mazda Raceway Laguna Seca in 2014.
Teammate Jonathan Bomarito turned a lap of 1:18.604 late in the 60-minute session that was good enough for second on the time sheets.
Ozz Negri was third quickest in the No. 60 Michael Shank Racing Liger JS P2 Honda with a lap of 1:18.699.
Ricky Taylor put the No. 10 Wayne Taylor Racing Corvette DP in fourth with a 1:19.055 lap.
Rounding out the top five was the No. 31 Action Express Racing Corvette DP of Dane Cameron, the only other DP in the top-five.
Top honors in the GT Le Mans class went to the Scuderia Corsa Ferrari 488 GTE of Alessandro Pier Guidi with a lap of 1:22.975.
One Ford and a Ferrari made up the top-three as Joey Hand was second in the No. 66 Ford Chip Ganassi Racing Ford GT followed by Toni Villander’s Risi Competizione Ferrari.
Richard Westbrook in the No. 67 Ford and Jan Magnussen in the No. 3 Corvette C7.R rounded out the top-five.
Renger van der Zande was the quickest man in Prototype Challenge in the No. 8 Starworks Motorsport Oreca FLM09.
The Dutchman set a best lap of 1:20.018 midway through the PC/GTD session but his co-driver Alex Popow stopped on track as the checkered flag came out.
Van der Zande was followed by the No. 54 CORE autosport entry of Colin Braun, who had a best lap of 1:20.310.
Tom Kimber-Smith ended up third with a lap of 1:20.840 in the PR1/Mathiasen Motorsports car after briefly leading the opening minutes of the session.
The No. 88 Starworks entry of Mark Kvamme brought out the session’s only red flag when she stalled near the Corkscrew with 9 minutes remaining.
In GTD, the No. 23 Team Seattle/Alex Job Racing Porsche 911 GT3 R of Alex Riberas was quickest with a lap of 1:25.560.
The No. 73 Park Place Motorsports Porsche of Patrick Lindsey and Joerg Bergmeister was second quickest, followed by the No. 33 Riley Motorsports Dodge Viper GT3-R of Jeroen Bleekemolen.
The second P/GTLM practice session gets underway at 2:20 p.m. PT, followed by another hour-long session for PC/GTD cars at 4:45 p.m.