Brabham BT21

The Brabham BT21 was an open-wheel formula racing car designed, developed and built by Brabham in large numbers in 1966 and delivered to private individuals; 110 were made. Most were Formula 3 cars, some were built for US Formula B as the 21B, and the Formule Libre versions ran as the 21C. It had a tubular space frame, a lightweight fibreglass body and a 997 cc naturally aspirated Cosworth MAE four-cylinder engine with 125 hp, driving the rear wheels through a Hewland five-speed gearbox, and weighed only 410 kg. Private drivers such as Peter Westbury did well with it in 1967. In 1968 it faced the new Tecno, so the BT21B gained wider wheels and a sturdier frame, and from 1969 the BT28 slowly replaced it.