In 2014, the JDC-Miller MotorSports made its debut in the new competition, United SportsCar Championship, which resulted from the merger of Rolex Sports Car Series and American Le Mans Series. At the first participation in this competition, the best result was the 3rd place in the race from Road America to the Prototype Challenge class. The main race drivers this season were Chris Miller and Stephen Simpson. In the 2015 season, the team finished three times on the podium, in the race at The Raceway on Belle Isle they finished in 2nd place, and in the 24-hour races at Daytona and Canadian Tire Motorsport Park they finished in 3rd place. Races were Mikhail Goikhberg, Chris Miller, Rusty Mitchell and Stephen Simpson. In the third season of this competition, with the name change in the WeatherTech SportsCar Championship, the JDC-Miller MotorSports achieves its first major victories, winning the 24-hour race at Daytona and Long Beach Street Circuit, finishing at the end of the season in position third in the general classification with pilots Mikhail Goikhberg and Stephen Simpson in the 2016 Prototype Challenge class.