Rahal, whose BMW Team RLL won the ALMS 2010 and 2011 team and manufacturer titles in the GT class, as well as last year's GT drivers' title with Joey Hand and Dirk Muller, said that bringing the two series together would ultimately strengthen sportscar racing in the US.
"As we've seen in Indy car racing, this is nothing but great news for the sport, for the teams and for the fans," said Rahal.
"It's a huge win for racing in general and sports car racing in particular. I commend [Grand-Am founder] Jim France and [ALMS owner] Don Panoz for finding a way to come together and doing what is best for the sport.
"I think that with the combined schedules, the might of ISC's marketing and the types of circuits we can focus on, it couldn't be any better for a series.
"I'm very, very enthused and excited about it and looking forward to seeing it all come together."
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