TWR initially undertook privateer work before securing factory contracts with Mazda and Rover. Walkinshaw's TWR-developed Mazda RX-7, driven by Win Percy, won the British Touring Car Championship in both 1980 and 1981. In 1982, TWR turned its attention to Jaguar, entering the Jaguar XJS in the European Touring Car Championship with considerable success. Success in touring cars led Jaguar chairman John Egan, who was eager to raise the marque's international profile following Jaguar's privatisation in 1984, to commission TWR to develop a full Group C prototype programme.
TWR's prototype campaign began in 1985 with the XJR-6, designed by Tony Southgate with a carbon-fibre chassis powered by a Jaguar V12 engine. The car formed the foundation for a series of XJR machines that would dominate the World Sportscar Championship (WSCC) through the late 1980s. The XJR-8 won the WSCC Teams' Championship in 1987, and the XJR-9 repeated that achievement in 1988 while also taking outright victory at the 24 Hours of Le Mans — the first Le Mans win for Jaguar since 1957. Andy Wallace, Johnny Dumfries, and Jan Lammers shared the winning car. Raul Boesel (1987) and Martin Brundle (1988) won the WSCC Drivers' Championship for TWR-Jaguar.
TWR also competed in the IMSA GT Championship in North America, initially alongside Bob Tullius's Group 44 team, before securing the sole Jaguar contract for both WSCC and IMSA by 1988. The team won the 24 Hours of Daytona in 1988 as well.
A second Le Mans triumph came in 1990 with the XJR-12, a development of the XJR-9. Martin Brundle, John Nielsen, and Price Cobb drove the winning car.
TWR developed its own turbocharged V6 engine for the XJR-10 (IMSA) and XJR-11 (WSCC) cars of 1989–1990, capable of substantially more power than the V12 but less suited to 24-hour endurance events. The final WSCC Jaguar was the XJR-14, the first car designed entirely by Ross Brawn. It won both the Drivers' and Teams' championships in 1991 — Teo Fabi taking the drivers' title — before Jaguar withdrew from the series due to rule changes deemed unfair by the major manufacturers.
Prominent engineers who developed their careers at TWR alongside Brawn and Southgate included operations director Roger Silman. Ian Callum served as design director from 1991 to 1999 and later designed the Jaguar XJR-15, the only road car ever fully designed and built by TWR. The XJR-15 was derived from the Le Mans-winning XJR-9 and sold to a select group of wealthy enthusiasts, who raced it in the Jaguar Intercontinental Challenge — a supporting series at Monaco, Silverstone, and Spa in 1991.
In 1984, TWR created TWR Sport to produce modified Jaguar XJ-S road cars. This led to a formal 50/50 joint venture with Jaguar in 1988 called JaguarSport, which went on to develop and produce the Jaguar XJ220 supercar at a new facility in Bloxham, Oxfordshire. Production ran from 1990 to 1993. When Ford purchased Jaguar in 1989, the relationship between Jaguar and TWR cooled; JaguarSport was liquidated in 1994 and the Bloxham factory repurposed for Aston Martin production. TWR took on the design and development of the Aston Martin DB7, designed by Ian Callum.
After Jaguar's withdrawal, TWR continued to win at Le Mans with other manufacturers. The WSC-95, a development of the XJR-14 platform fitted with a Porsche engine, won the 1996 and 1997 24 Hours of Le Mans in the hands of Joest Racing. TWR also helped Nissan develop the R390 GT1 for the 1998 Le Mans, where all four Nissan entries finished, the best placing third overall.
TWR's entry into Formula One as a major shareholder of the Arrows team from 1996 proved costly. Despite a near-win at the 1997 Hungarian Grand Prix with Damon Hill, Arrows attracted little sponsorship and was liquidated, pulling TWR down with it. The firm closed in 2002. Its UK technical centre at Leafield subsequently housed the Super Aguri F1 and Caterham F1 teams.
The TWR-Jaguar programme restored Jaguar to the top of endurance racing and remains one of the most celebrated partnerships in the history of the sport. The light blue, white, and green Silk Cut livery worn by the XJR cars in their World Sportscar Championship and Le Mans appearances became among the most recognised colour schemes in motorsport history.