Formula Atlantic is a specification of open-wheel racing car developed in the 1970s. It was used in professional racing through the IMSA Atlantic Championship until 2009 and is currently primarily used in amateur racing through Sports Car Club of America Formula Atlantic. History The history of Formula Atlantic begins with the SCCA Formula B class, created in 1965 for single-seat formula cars with engines not exceeding 1600cc in capacity. Prior to Formula Atlantic, professional Formula B races were held in the United States from 1965 to 1972, firstly with the SCCA's poorly supported Formula A, then as part of the SCCA Grand Prix Championship in 1967 and 1968 and then in their own independent series from 1969 to 1972. Formula Atlantic as a class evolved in the United Kingdom in 1971 from the US Formula B rules, with 1600cc production-based twin-cam engines (initially Cosworth Mk.XIII based on Lotus-Ford Twin Cam and then Cosworth BDD, however other engines like Alfa Romeo were also eligible). Conceived by John Webb of Brands Hatch (who would later also develop the Sports 2000 class) as a category for national competitors with the performance near a Formula Two car but running costs at or below that of a contemporary Formula Three car. A single Yellow Pages championship ran in 1971-2, with a rival BP backed series appearing in 1973. 1974 saw the BP series changing sponsor to John Player, and the Yellow Pages series becoming backed by John Webb's MCD organisation and Southern Organs; in practice most top drivers competed in both series and there were no date clashes. Only one series ran in 1975-6, in the final year taking the title Indylantic and adopting Indianapolis-style single-car qualifying. But the formula was under threat from Formula Three and no series ran in 1977-78. A BRSCC-organized club racing series returned in 1979 with initial backing from Hitachi and continued to 1983, with diminishing grids and few new cars appearing. As a result of its similarity to Formula Two and Formula Three in terms of chassis regulations, Formula Atlantic typically used chassis closely related to these cars—with performance somewhere in between the two—so most of the manufacturers were familiar from those classes, particularly the likes of Brabham, Lotus, March, Chevron early on, with Ralt and then Reynard later. US manufacturer Swift came to displace the British imports and dominate in North America. Several smaller marques also appeared. The