With 800 tracks in 49 states, 30 million fans, and a billion dollars a year in revenue, dirt track racing is the biggest sport you've never heard of. In this energetic hour, CNN takes you inside this full-speed world of "bad fast" cars to meet the stars, watch the races, and join the millions for whom dirt track racing is a way of life. Before NASCAR became the largest growing spectator sport in the nation, drivers raced on dirt - and still do. In tracks across the country, competitors ranging from long-timers to weekend warriors, local mechanics to consummate pros race roaring racing machines engineered nearly from scratch before legions of committed fans