The 1990 Australian Manufacturers' Championship was open to manufacturers of cars complying with CAMS Group 3A Touring car regulations and was contested over a four-round series.
Rounds were run concurrently with those of the 1990 Australian Endurance Championship.
"Australian Motor Racing Year, 1990/91" suggests that the championship win was tied between Ford & Holden however both the CAMS Manual of Motor Sport (post 1990 editions) and www.camsmanual.com.au state that the title was awarded solely to the Ford Motor Company of Australia.
References1990 Australian Manufacturers' Championship Wikipedia
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