Formula Junior

Formula Junior is an open wheel formula racing class first adopted in October 1958 by the CSI (International Sporting Commission, the part of the FIA that then regulated motorsports). The class was intended to provide an entry level class where drivers could use inexpensive mechanical components from ordinary automobiles. The idea to form the new class came from Count Giovanni "Johnny" Lurani who saw the need of a class for single-seater racing cars where younger drivers could take their first steps. It is often speculated that this class was founded as a reaction to Italy's lack of success in the 500cc Formula Three, and although Italian marques dominated the first year of the formula, they were soon overtaken by British constructors.

The rules for the class required the cars to be powered by production-based engines with a volume of 1000 cc with a 360 kg (792 lb) car or 1100 cc with a 400 kg (880 lb) car – in practice the latter was used in almost all successful FJs (the USA adopted other cc/weight ratios but they were rarely used). Parts like engine block, head and cylinders had to come from a production car; single or twin overhead camshafts, limited slip differentials and modifications to the number of main bearings were all forbidden. The brakes and transmission also had to be production-based. Constructors were allowed to increase the number of gears, but only inside a production gearbox casing. Formula Junior was also the first racing class to require roll cages. In Italy the popular Fiat 1100 engine was the obvious choice and in 1958 there were few other suitable engines in Italy; elsewhere the 1000 cc Mini engine as well as the DKW and the Saab three-cylinder two-stroke engines were obvious choices, as was the new oversquare Ford engine from the 105E Anglia. The first Italian FJ cars were very much in the front-engined tradition of contemporary Grand Prix cars; the first international Formula Junior championship in 1959 was won by the Swiss driver and engineer Michael May in an Automobili Stanguellini. The British constructors were initially not particularly interested; the 500cc Formula Three was still just about viable, and small-capacity sports car racing had become the accepted route into racing. As the formula gathered momentum, though, constructors started to take note.

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