The Chevron B31 was an evolution of the Chevron B26, designed by Chevron Cars Ltd's founder Derek Bennett in 1975. It featured a slightly redesigned bodywork, but retained the basic aluminium monocoque chassis of its predecessor. The bodywork was made from fiberglass. Initially, the B31 was fitted with a 2-litre Hart 420R straight-four engine producing 290 hp, but it was later used with a variety of engines including the 3-litre Cosworth DFV V8, 2-litre Cosworth FVD/Cosworth BDG straight-four engines, and the 2-litre BMW M12 straight-four. The 420R engine produced a maximum power output of 290 hp at 9500 rpm, and power was transmitted to the rear wheels via a Hewland 5-speed manual transmission.
The car’s suspension featured double wishbones, coil springs over dampers with an anti-roll bar at the front, and single top links, twin lower links, twin trailing arms, coil springs over dampers with an anti-roll bar at the rear. It used ventilated disc brakes all around, and rack-and-pinion steering. Weighing 580 kg, the B31 had a power-to-weight ratio of 0.5 hp/kg.
The B31 made its racing debut at the 1000 km of Mugello, part of the World Championship for Makes. KVG Racing entered John Hine and Ian Grob in a B31, and Team Italiano Chevron also ran the car with Eris Tondelli and Mauro Nesti. Team Italiano Chevron used a 1.3-litre Cosworth straight-four engine, while the KVG Racing car had the 2-litre Hart 420R. KVG Racing won the Sports 2000 class, finishing fifth overall. At the 800 km of Dijon, KVG Racing took third overall and the Sports 2000 class victory. At the 1000 km of Monza, Grob crashed in practice, but “Bramen” and Pasquale Anastasio won the Sports 1300 class, finishing 13th overall, while “Bramen” also partnered Giancarlo Gagliardi in a car entered by Scuderia Citta dei Mille. At the 1000 km of Spa, KVG Racing finished third in the Sports 2000 class, and 14th overall. At the 1000 km of Pergusa, KVG Racing finished ninth overall. At the 1000 km of Nürburgring, Fisons Racing joined KVG Racing, but neither car had a successful race. Four B31s were entered in the European 2-Litre Championship opener at Brands Hatch; Hine won the first heat, and Grob finished fourth. In the second heat, Grob finished third, while Hine retired. At the 1000 km of Zeltweg, Team Fisons finished 13th overall, and sixth in class. At the Hockenheim round of the E2LC, Raymond won the event outright.
The B31’s first appearance of 1976 was at the 300 km of Nürburgring, part of the World Sportscar Championship, but none of the entered cars finished. At the 4 Hours of Monza, five B31s were entered, but none finished either, with engine failures and cooling system issues plaguing the entries. The 500 km of Imola saw only one B31 entered, but it retired due to gearbox failure. The car did win non-championship races at Zolder, an Interserie race at Zolder, and a British Sports Car Championship round at Thruxton.
The 1977 World Sportscar Championship season began with retirements at Dijon and Monza. At the 500 km of Imola, Francisci and Fiaccadori finished eighth overall, and fifth in the Sports 2000 class. The car was entered in the 24 Hours of Le Mans for the first time, but retired due to a fuel pump failure after 21 laps. At the 500 km of Le Castellet, Jassaud and Henry won the Sports 2000 class.
The 1978 season saw the introduction of the European Sportscar Championship. Raymond finished ninth overall, and second in the Sports 2.0+ category, at the 300 km of Nürburgring. At the 320 km of Monza, several cars failed to qualify, and the one that did retired due to engine problems. The B31 was entered in the 24 Hours of Le Mans, but retired. Ridolfi and Grassi finished sixth at the Coppa Florio Pergusa.
In 1979, the World Championship for Makes replaced the European Sportscar Championship. Ridolfi and Marazzi finished fourth overall, and won the Sports 1600 category, at the 1000 km of Monza. Götz finished second in the third round of the Interserie championship at Nürburgring.
Götz attempted to enter the 1000 km of Monza, but did not compete. Götz and Blanckley finished 15th overall, and won the Sports 2000 category, at the 1000 km of Nürburgring. Gellini and Grassi retired at the 6 Hours of Vallelunga.
By 1981, the B31 was used less frequently. Gellini and Ridolfi retired early at the 1000 km of Monza. Götz finished seventh overall, and fourth in the Sports 2000+ class, at the sixth round of the Interserie championship at Nürburgring.
From 1982, the B31 competed primarily in the Interserie championship. According to research findings, Götz achieved several class results in the Interserie during this period.
After a period of inactivity, two B31s were entered in a non-championship race at Kyalami in 1987. MacQuillan and Williams entered the car in several BRDC C2 Championship races in 1988 and 1989, achieving a fifth-place finish at Brands Hatch in 1988. MacQuillan and Williams entered one final race in 1990, but failed to start. The B31 was retired after this event.