Shuman won the Turkey Night Grand Prix, a major event in the midget cars series, on eight occasions in 1979, 1980, 1981, 1982, 1984, 1987, 1992 and 1993. He won the Knoxville Nationals in 1979. He tried his hand at Championship Car racing in 1980 and finished in 11th place in his first race at Ontario Motor Speedway in April of that year. However, a month later he failed to qualify for the 1980 Indianapolis 500. In 1981, Shuman sided with USAC in their split with CART and Shuman entered in two dirt track races on USAC's "Gold Crown" Champ Car calendar, failing to qualify for one and finishing 15th in the other. The following season in 1982 Shuman notched his best Champ Car finish at the Illinois State Fairgrounds Racetrack with a 5th place and competed in two other dirt track Gold Crown races. He made another appearance in 1983 before the series ended. Shuman continued to race sprint cars during his foray into Champ Car and still makes occasional appearances in major sprint car events to this day.