It was only from the beginning of the "Group A" category in Australia in 1985 that the headline teams started appearing in the series on a more regular basis, with part of the reason being that as Group A was new to Australia in 1985, the AMSCAR Series gave teams valuable testing under race conditions (also because from 1985 Amaroo would hold an annual round of the ATCC). Frank Gardner's JPS Team BMW and its drivers Jim Richards and Tony Longhurst dominated from 1985 to 1987 (Richards in the 635 CSi was unbeaten at Amaroo in 1985 winning all 12 AMSCAR races, the ATCC round and the Endurance Championship race), while Gibson Motorsport, first with Nissan and later with Holden, also contested the series in the later years of Group A and into the new 5.0L V8 formula introduced in 1993, with Jim Richards winning in the team's Nissan Skyline GT-R in 1992 while Mark Skaife won for Gibson driving a Holden VP Commodore in 1993. Other top line teams to contest the AMSCAR series after the switch to Group A were Peter Brock's Holden Dealer Team (later known as Mobil 1 Racing), Dick Johnson Racing, 1988 series winner Colin Bond's Caltex CXT Racing Team, Tony Longhurst's Benson & Hedges team (evolved from JPS Team BMW), as well as Robbie Francevic's Volvo team.