Ambrose confirmed his 2015 plans on Sunday night, saying he will drive for Team Penske in V8 competition.
Penske will partner with Dick Johnson Racing to field a Ford for Ambrose, a two-time champion in the series who won 26 of 65 events from 2001-2005 before leaving his home country to embark on a NASCAR career.
Ambrose had said on Saturday that he would not return to Richard Petty Motorsports. A two-time winner in Cup at Watkins Glen, Ambrose said his Cup career had reached a plateau and he had come to NASCAR with the idea that if his learning curve stagnated or if he wasn't competitive, he would return to his home country.
"This is a great opportunity to return home to a place that I love in a series where I’ve experienced a lot of success,” Ambrose said. “It will be an honor to race for two motorsport legends in Roger Penske and Dick Johnson.”