Brothers Jordan and Ricky Taylor maintained their 100% victory rate with the Cadillac DPi-V.R chassis by winning an eventful sprint contest on the streets of Long Beach.
Jordan Taylor sealed a third straight win for the WTR squad with a late-braking manouevre on the outside of turn one to get past Ryan Dalziel in the ESM Nissan-Onroak DPi.
Taylor went on to win by a margin of 6.349 seconds, with Dalziel finishing second ahead of Jonathan Bomarito's Mazda DPi.
Dalziel unexpectedly took the lead during the final round of pit stops with 45 minutes to go when his team applied less fuel having already made a service under caution.
That brought the ESM car out in front of the Cadillac and Mazda entries that had dominated the opening portion of the race.
However, Taylor caught up with Dalziel during the final sprint to the flag and made the crucial pass with less than five minutes to go.
Finishing order: IMSA Long Beach
Incidents impact GTLM result
The 100-minute sprint was heavily disrupted by incidents and stoppages, with the safety car making five appearances in total.
Both Action Express Racing Cadillac DPis were affected by off-track moments, most notably that of defending IMSA champion Dane Cameron who made heavy contact with the turn eight wall to trigger the final safety car intervention.
The #5 Action Express machine also hit trouble, losing two laps when João Barbosa pitched the car into the wall at turn nine whilst negotiating a GTD car.
One incident on the final lap decided the result of the GT Le Mans category as the then-leading Corvette of Antonio Garcia became trapped behind a blockade of stationery GTD cars.
That allowed the sister Corvette, driven by Tommy Milner, to sneak through and take the chequered flag.
Milner, who shared the #4 C7.R with Oliver Gavin, was followed through by Ryan Briscoe in the #67 Ford and Kevin Estre in the #912 Porsche to complete the podium. Garcia recovered to finish fifth, having taken over the car from pole-sitter Jan Magnussen.
Much of the GTLM contest had been led by the BMW M6 of Martin Tomczyk and Bill Auberlen, but a mechanical failure for Tomczyk in the closing stages meant the car had to retire. Alexander Sims brought the sister BMW through to a fourth-place finish.
In GT Daytona, Mercedes scooped a one-two result to complement its maiden IMSA victory at the 12 Hours of Sebring last month.
Gunnar Jeanette and Cooper MacNeil emerged from 13th on the class grid to take victory ahead of Jeroen Bleekemolen and Ben Keating, whilst Alessandro Balzan and Christina Nielsen took third in their Ferrari.
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