Swindell comes from a racing family. His father Sam was a successful driver, and his brother Jeff has remained an active sprint car competitor. Swindell's nickname, "Slammin Sammy," reflects the aggressive style that defined his approach to dirt-track racing.
Swindell became one of the defining figures of the World of Outlaws sprint car series from the moment it gained prominence in the late 1970s. He finished ninth in points in his first full season in 1978, then steadily climbed the standings. In 1979 he won 11 races and finished second. He claimed his first championship in 1981 driving the Nance Speed Equipment No. 1n house car, winning 28 races that season — a career high. He repeated as champion in 1982 with 14 wins. That 1981 season also brought a memorable achievement when Swindell took the wings off his car to win the prestigious Pacific Coast Nationals at Ascot Speedway.
After several strong but non-championship seasons through the 1980s, Swindell won his third World of Outlaws title in 1997 driving his own Channel Lock-sponsored No. 1 team car, logging 19 wins. His four runner-up finishes — in 1979, 1984, 1988, and 2000 — underscore the consistency he maintained across generations of competitors.
By September 2020, Swindell had recorded 394 World of Outlaws Sprint Car wins.
Swindell made his NASCAR Winston Cup debut in the 1985 Atlanta Journal 500. In 1985 and 1986 he also competed in the CART Indy car series, and in 1987 he attempted to qualify for the Indianapolis 500 in a March-Pontiac but failed to make the field.
In 1991 Swindell planned a full-time move to the NASCAR Winston Cup Series with Moroso Racing, targeting Rookie of the Year honors. The effort collapsed early: he was released after multiple spins during Speedweeks and another crash in qualifying at Richmond International Raceway. He returned to sprint cars.
He ran a limited NASCAR Busch Series schedule in 1993 before the team folded mid-season, and then contested the full inaugural 1995 NASCAR Craftsman Truck Series season for Akins-Sutton Motorsports, finishing 12th in points with five top-ten finishes.
Swindell became a five-time winner of the Chili Bowl Midget Nationals, at the time the only driver to win the event more than three times. His son Kevin later won four straight Chili Bowl titles beginning in 2013.
In 2007, Swindell was in his 35th consecutive year of racing, now competing alongside his son Kevin. He announced retirement in August 2014 but quickly reversed course, signing with CJB Motorsports out of Telford, Pennsylvania in 2015 to run a partial schedule. He continued picking and choosing events in subsequent seasons.
After a long winless stretch, Swindell scored two wins in 2023 — his first sprint car victories since 2018. He added another win in 2025 and in July 2025 raced a pavement sprint car for the first time since 1992.
Swindell is regarded as one of the greatest sprint car drivers of the modern era. His combination of outright speed, mechanical insight, and longevity — remaining competitive into his seventh decade of life — set him apart. He is known as an innovative setup man and experimenter with vehicle technology, qualities that extended his effectiveness well beyond a normal racing career. His family — father, brother Jeff, and son Kevin — form one of the prominent racing dynasties of American dirt-track competition.