Firth was known affectionately as the Fox, due to his uncanny ability to come up with ideas to out manoeuvre the opposition.

He became involved in the sport after serving in World War II, by preparing the 1948 Australian Grand Prix-winning BMW 328 for Frank Pratt.

In the 1950s he successfully competed in races and hillclimbs in 356 Porsches and between 1953 and 1962 won the tough Alpine rally five times.

Firth and Bob Jane teamed up to win the 1961 Armstrong 500 race for production cars at Phillip Island in a Mercedes 220 SE and they followed up with their second win in 1962 in an XL Ford Falcon.

At this time Firth was under contract to the Ford Motor Company, preparing its race and rally cars in his own workshop.

The following year the race moved to Bathurst and Firth and Jane made it a hat-trick by winning in a Mark 1 Ford Cortina GT and in 1964 Firth and Graham Hoinville won the Ampol Round Australia trial in a Cortina GT.

The Firth-Hoinville combination also won the inaugural Southern Cross rally in 1965 in a Cortina GT

In 1967 Firth won the Gallaher 500 mile race at Bathurst in the first of the Falcon GTs with Fred Gibson and the following year Firth built three XT Falcon GTs for the gruelling London to Sydney marathon with the cars finishing third, sixth and eighth and claiming the prestigious teams prize.

That year Firth also won the Australian Rally championship but in 1969 his association with Ford came to an end when the company decided he was too old for the position.

It didn't take long for the opposition to pick him up and the Holden Dealer Team was formed as a way of getting around General Motors' no involvement in motor sport policy.

One of the first things Firth did as manager was to secure the services of a couple of aspiring young guns in Colin Bond and Peter Brock who would go on to be champions and household names.

Bond and Tony Roberts won the 1969 Hardie Ferodo 500 in a Holden Monaro GTS 350 with Brock and Des West finishing third in the second team car.

Over the next eight years the HDT under Firth scored many race and rally victories including the Southern Cross rally in 1970 and 1971, the 1971 South Pacific Touring car series, 1971 Sandown 250, 1971 Autolite Rallycross series and regular round wins in the Australian Rally Championship in 1971, 1972 and 1974 by Bond in a variety of Toranas.

Brock scored his first of nine Bathurst wins in 1972, the 1973 and 1974 South Pacific Touring Car series, the 1973 Sandown 250 and the 1974 Australian Touring Car championship.

Bond backed that up by winning the 1975 ATCC and HDT drivers teamed up to win the 1971, 1973 and 1974 the Australian Manufacturers championship for GMH.

Firth retired as team manager of the HDT at the end of 1977 but continued his involvement in the sport as the National Chief Scrutineer from 1979 till 1981.

Firth was often referred to as a bush engineer but there is no doubt he was a great deal smarter than many gave him credit for.

As a measure of his outstanding contribution to the sport, Firth was inducted into the V8 Supercar Hall of Fame in 2007.