Peter Agg established Trojan in the early 1970s to build customer McLaren M8E CanAm cars in a factory in Croydon in the southern suburbs of London. There were plans for a similar deal with single-seaters for F5000 versions of the M19 and the M21 Formula 2 car but that fell through and so Trojan took on Ron Tauranac, who had just left Brabham, to design the Trojan T101 Formula 5000 car. The first of these appeared in March 1973 and several were raced in Formula 5000 that year, notably by Jody Scheckter, Bob Evans and Keith Holland. The Trojan T102 followed in Formula 5000 in 1974 and the T103 Formula 1 car - a T102 chassis fitted with a Cosworth DFV engine - was run in selected Grand Prix that year for driver Tim Schenken.
The team made its F1 debut at the Spanish GP and appeared at eight races in total, Schenken qualifying for sixth of them. His best result was 10th in both Belgium and Austria. The budget was exhausted by September and the team closed down after the Italian GP.