John Wyer had managed the GT40 development programme at Ford Advanced Vehicles from 1963, overseeing the design and production of the Mk I cars at a factory in Slough near Heathrow Airport. When Ford closed FAV at the end of the 1966 season, Wyer and John Willment took over the Slough factory, continued to build production GT40s on Ford's behalf, and registered J.W. Automotive Engineering Ltd. Despite widespread assumption that "JW" stood for John Wyer, the initials in fact represented John Willment, as Willment's brother-in-law Hans Herrmann later confirmed. Wyer was the better-known figure at circuits and was the face of the team's racing operations.
The team's association with Gulf Oil, brokered with team manager J-O Bockman, brought the iconic light-blue and orange livery that would become among the most recognisable colour schemes in motorsport history.
JWA entered the 1967 season with the Ford-powered Mirage M1 prototype, which won the 1000 km of Spa. When a rule change for 1968 limited prototype engine capacity to 3.0 litres — the same limit as Formula One — the fast, large-displacement prototypes were effectively banned. However, the existing Group 4 sports car category allowed cars like the Ford GT40 Mk I, of which more than 50 had been built, to race with engines of up to 5.0 litres.
Wyer revised the 4.7-litre Ford V8 in the GT40, enlarging it to 4.9 litres and addressing the head gasket failures that had plagued earlier configurations. The result was a reliable, powerful package. Despite the Porsche 907 being considered the likely title favourite, the JWA Gulf GT40s won four of the season's championship rounds and claimed the 1968 International Championship for Makes. The crowning achievement came at the 1968 24 Hours of Le Mans, where Pedro Rodriguez and Lucien Bianchi won in the team's Gulf-liveried Mk I.
In 1969, Wyer repeated the Le Mans victory with Jacky Ickx and Jackie Oliver, who outpaced the remaining Porsche 908s with the same GT40 Mk I chassis that had won the previous year. The 1969 race is celebrated for Ickx's protest against the traditional Le Mans sprint start — he walked to his car and fastened his seatbelt before driving, having witnessed the death of a marshal in a previous race. Despite starting last, he and Oliver won by a matter of seconds over the leading Porsche.
As the GT40 became obsolete under the new regulations, Wyer was approached by Porsche to manage its works racing programme. JWA Gulf became the factory's primary partner from 1970, racing the Porsche 917 alongside the smaller 908 for twisty circuits. Wyer's drivers — Jo Siffert, Brian Redman, Leo Kinnunen, Pedro Rodriguez, Richard Attwood, Herbert Mueller, and Derek Bell — earned seven of Porsche's nine championship victories in the 1970 season and five of eight in 1971. The Gulf Porsche 917K, with its distinctive wedge-shaped Kurzheck tail developed partly with JWA's input, became one of the most dominant endurance racing cars in history. The 917K that won in Steve McQueen's 1971 film Le Mans wore Gulf colours, further cementing the team's iconic status. JWA's best Le Mans result in the Porsche era was second place in 1971.
After the 5.0-litre sports car regulations were retired at the end of 1971 and Porsche withdrew from European endurance racing, Wyer developed a new generation of Gulf Mirage prototypes powered by the Formula One Cosworth DFV engine. The DFV had been considered unsuited to endurance work due to vibration, requiring significant modification for the demands of long-distance racing. After three years of development and competitive effort, Jacky Ickx and Derek Bell delivered what would prove to be John Wyer's final Le Mans victory in 1975, winning overall with the Gulf Mirage GR8.
John Wyer retired from motor racing competition in 1976 and sold the team to Harley Cluxton's Grand Touring Cars operation. Wyer died in Scottsdale, Arizona, on 8 April 1989. J.W. Automotive's legacy encompasses four Le Mans outright victories (1968, 1969, 1975, and a shared legacy in the 1970 and 1971 Porsche campaigns), two manufacturers' championships, and the enduring visual identity of the Gulf Oil livery — a colour scheme that remains one of the most reproduced and celebrated in motorsport history.