Get automotive news, DIY tips, market trends, in-depth car profiles, and more right in your email inbox. Over a dozen race cars stormed past a fluttering green flag. This technicolor procession of noise and nostalgia meant that the International Race of Champions, or IROC for short, was in town. Trophies—and bragging rights—were on the line. Stick around long enough in Concord, North Carolina, and chances are you’ll hear the hair-raising rumble of an uncorked V-8 at full song.