Seton was born on 5 October 1936 and overcame polio as a child. He went on to compete in the Bathurst 500 and later the Bathurst 1000 at Mount Panorama on 22 occasions, starting every year from 1963 to 1984 and completing the race in fifteen of those starts — a record of consistency that few Australian drivers have matched at a single event.
Seton's outright win came in 1965, when he and co-driver Midge Bosworth drove a Ford Cortina GT500 to victory in the Bathurst 500. The win placed him among the select group of Australian drivers to have taken the outright spoils at Australia's most demanding circuit.
Seton was particularly noted in the mid-1970s for his mastery of the Ford Capri. He won his class at Bathurst in 1976, 1977, and 1980, co-driven on each occasion by Don Smith. Beyond Bathurst, he won the Sun-7 Rothmans 3-Litre Series three times at Amaroo Park during the same period, reinforcing his reputation as one of the leading Capri exponents in Australian competition.
For his 21st Bathurst start in 1983, Seton's co-driver was his son Glenn Seton, who was making the first of what would eventually become 25 Great Race starts. Glenn went on to win the Australian Touring Car Championship twice and became one of the most prominent figures in Australian V8 Supercars. The father-and-son pairing was leading Class B by more than a lap when their Ford Capri's engine failed, resulting in a DNF. Seton's final Bathurst appearance came in the 1984 James Hardie 1000, where he drove a Group A Ford Mustang alongside longtime co-driver Don Smith, finishing 20th outright and 3rd in Group A.
After stepping back from top-level driving, Seton established a second highly regarded career as a race engine builder. From 1986 to 1988 he built the turbocharged engines for the Peter Jackson Nissan Team. When Glenn formed Glenn Seton Racing in 1989, Barry joined as chief engine builder, overseeing preparation of the team's Ford Sierra RS500s. He continued in that role as the team transitioned to the V8 Ford Falcon in late 1992. Alongside his work for his son's team he built customer engines for various privateer V8 Supercar competitors. He left Glenn Seton Racing after 1995 and was recruited by Longhurst Racing as chief engine builder from 1996.
In later years Seton continued to compete in historic touring car events in his Historic Touring Car Mk.I Ford Capri and built Capri and Holden Torana engines for cars competing in Group 2 of the Touring Car Masters series, including the engine for Glenn's Group 1 1973 Ford Falcon XB Hardtop.
Barry Seton died on 17 April 2026 at the age of 89. His 22 Bathurst starts represent a sustained commitment to Australia's most prestigious endurance race that spanned more than two decades. Through his son Glenn and through the many engines he built for competitive teams across the 1980s and 1990s, Seton's influence on Australian motorsport extended well beyond his own driving career.