Australian Formula 3

Australian Formula Three was an Australian open-wheel motor racing category introduced by the Confederation of Australian Motor Sport (CAMS) in 1964. The category was contested until the end of the 1977 season and represented the lowest tier of CAMS-sanctioned formula car racing during that period. Although based on FIA Formula 3 regulations, the Australian category evolved independently and developed significant overlap with Australian Formula Two prior to its discontinuation. Australian Formula Three was never awarded national championship status, instead being contested through state championships and inter-state series such as the Stillwell Series. Introduction and early regulations (1964–1968) Australian Formula Three was introduced by CAMS in 1964 as a cost-effective entry-level category for amateur drivers, positioned below the Australian National Formula, the Australian 1½ Litre Formula, and Australian Formula Two. The category was initially based on contemporary FIA Formula 3 regulations. Cars were restricted to production-based engines of up to 1000 cc, with overhead camshaft engines prohibited, effectively limiting powerplants to pushrod designs. The emphasis was on simplicity, reliability, and low operating costs. Chassis were typically spaceframe designs, often locally constructed or adapted from European Formula 3 designs, and commonly used production-derived components for suspension, braking and transmissions. Regulatory expansion (1969–1971) For the 1969 season, CAMS amended the regulations to increase the maximum engine capacity to 1100 cc and removed the prohibition on overhead camshaft engines. These changes broadened the range of eligible engines and marked the beginning of a steady increase in performance. During this period, Australian Formula Three cars began to approach the performance of earlier Formula Two machinery, particularly at tighter circuits, while remaining production-based in concept. 1300 cc era and peak participation (1972–1977) From 1972, the engine capacity limit for Australian Formula Three was increased to 1300 cc. Engines were required to remain production-based, using pushrod or single overhead camshaft valve actuation, with carburetion mandatory. By the mid-1970s, the Toyota Corolla engine had become the most popular Formula Three powerplant, producing approximately 135 bhp at 8,000 rpm. With minimum weights of around 350 kg, the fastest Formula Three cars were capable of lap times competitive with slower Australian Formula Two cars, which typically weighed around 400 kg and produced 200–210 bhp from 1600 cc engines. Despite lacking national championship status, Formula Three enjoyed strong participation and regular racing in Victoria, New South Wales, and South Australia, with prominent series including the Stillwell Series providing inter-state competition. The category was dominated in the mid-1970s by Brian Sampson and Brian Shead, whose Cheetah chassis became the most successful and widely used Formula Three car in Australia. Other leading competitors during 1976 and 1977 included Gary Scott, Peter Macrow, and Terry Finnigan, all driving Cheetahs. For 1978, Australian Formula Two regulations were substantially revised to incorporate many of the technical characteristics of the former Formula Three category, including production-based engines of up to 1.6 litres, carburetion, and restrictions on valve actuation. The revised Formula Two cars were visually and mechanically similar to the final generation of Australian Formula Three machinery, effectively merging the two categories. ==History – The Second Era==