Richard Westbrook and Michael Valiante (#90 VisitFlorida.com Racing Corvette DP) came to Mosport leading the championship standings following their win in the previous round at the 6 Hours of the Glen. GTLM was tied between the #3 Corvette Racing C7.R (Jan Magnussen, Antonio Garcia) and the #25 BMW Team RLL Z4 (Bill Auberlen, Dirk Werner). John Bennett and Colin Braun (#54 CORE autosport) led Prototype Challenge by just 1 point over Mike Guasch and Tom Kimber-Smith (#52 PR1/Mathiasen Motorsports).
Ricky Taylor (#10 Wayne Taylor Racing Corvette DP), who crashed out from the lead at the Glen, started on pole with Christian Fittipaldi (#5 Action Express Racing Corvette DP) next to him. These two ran 1-2 in the early laps, followed by Valiante. Nick Tandy (#911 Porsche North America 911) claimed the GTLM pole -- the first driver to win two GTLM poles since USCC competition began -- and led in the early going over Werner and Lucas Luhr (#24 BMW). James French led PC in the #38 from Performance Tech Motorsports, followed by Bennett and Guasch.
With 2 hr 27 min. left in the 2:45-race the prototype leaders caught up with the back of the GTLM field and started working through the traffic. Fittipaldi passed Taylor on track with 2:05 to go. A full-course caution came out at the 2:02 mark. Both the #5 and #10 pitted under the yellow, Joao Barbosa and Jordan Taylor assuming the respective driving duties. Patrick Pilet took over for Tandy in the #911 Porsche.
The green flag flew with 1:50 left, Dane Cameron (#31 Action Express) leading Scott Pruett (#01 Chip Ganassi Racing Ford-Riley) and Oswaldo Negri Jr. (#60 Michael Shank Racing Ligier JS P2-Honda), all of whom stayed out during the yellow. Pruett, however, needed to serve a stop-and-go +1.00 min penalty for entering the pits when they were closed. Pilet led GTLM followed by Werner and Giancarlo Fisichella (#62 Risi Competitzione Ferrari 458 Italia).
Pruett’s penalty moved Negri into P2 and Barbosa into third. Camron pitted near the 1:30 mark, moving the Ligier to the front. Barbosa ran second, Valiante third. Barbosa made an unscheduled stop with 1:10 to go to replace a tire, moving Valiante to second and Taylor to third. Negri pitted from the lead 1 min later, leaving a Top 3 of Valiante, Taylor, and Cameron.
Taylor pitted at 1:06 and Valiante one lap later, Richard Westbrook taking over. Pilet pitted from the GTLM lead, Tandy retaking the wheel, while Auberlen took over for Werner in the BMW. The two cars returned to competition in that order. Barbosa led Negri and Jordan Taylor with 50 min to go. Tandy led GTLM over Auberlen and John Edwards in the #24.
Negri pitted with 45 min left and failing power steering. The #90 pitted one lap later for new tires, with the #10 following suit but taking left-side tires only. The #5 came in with less than 42 min to go, taking a full set of new rubber. With 37 min left the class leaders were Cameron, Braun, and Tandy.
Cameron led Barbosa by 18 sec, and Negri by 28 with 22 min left. Taylor passed Negri on track with 11 min. 30 sec. left. Cameron was pushing to build enough of a margin to make one more stop and still keep the lead, opening a 33.5 sec lead on Taylor, Barbosa having already pitted. Fuelling problems, however, saw him come out behind the #10.
Cameron cut 0.5 sec off Taylor’s lead on the next lap, dropping it to 1.6 sec. with less than 6 min to go. Taylor locked up with 3:20 left and Cameron closed but couldn’t make it past in the final laps. Negri finished P3. Braun took the PC victory, with Tandy topping GTLM ahead of Edwards and Garcia.