In 1972, he bought his first race car, from Andy Granatelli. He raced a Formula Ford in 1972, and then bought a midget car in 1974 from Gary Bettenhausen. He then competed in USAC midgets from 1975–83. Miller's best race came in 1980 when he qualified 5th out of 93 cars for the annual "Hut 100" at the Terre Haute Action Track, a dirt race that featured 33 starters in 11 rows of three like Indy and also sported several top Indy drivers of the time. He considers that race the highlight of his career, however, he blew his engine and dropped out.