Bruce McLaren made the team's Grand Prix debut at the 1966 Monaco race (of the current Formula One teams only Ferrari is older). His race ended after nine laps due to a terminal oil leak. The car was the M2B designed by Robin Herd, but the programme was hampered by a poor choice of engines: a 3.0-litre version of Ford's Indianapolis 500 engine and a Serenissima V8 were used, the latter scoring the team's first point in Britain, but both were underpowered and unreliable. For Bruce decided to use a British Racing Motors (BRM) V12 engine, but due to delays with the engine, was forced initially to use a modified Formula Two car called the M4B powered by a 2.1-litre BRM V8, later building a similar but slightly larger car called the M5A for the V12. Neither car brought great success, the best result being a fourth at Monaco.