In structure the MGB was an innovative, modern design in 1962, utilizing a monocoque structure instead of the traditional body-on-frame construction used on both the MGA and MG T-types and the MGB’s rival, the Triumph TRseries. However components such as brakes and suspension were developments of the earlier 1955 MGA with the B-Series engine having its origins in 1947. The lightweight design reduced manufacturing costs while adding to overall vehicle strength. Wind-up windows were standard, and a comfortable driver’s compartment offered plenty of legroom. A parcel shelf was fitted behind the seats.

The MGB achieved a 0-60 mph (96 km/h) time of just over 11 seconds. The three-bearing 1798 cc B-Series engine produced 95 hp (71 kW) at 5,400 rpm – upgraded in October 1964 to a five-bearing crankshaft. The majority of MGBs were exported to the United States. In 1975 US-market MGB engines were de-tuned to meet emission standards, ride height was increased by an inch (25 mm), and distinctive rubber bumpers were fitted to meet bumper standards.

The MGB was one of the first cars to feature controlled crumple zones designed to protect the driver and passenger in a 30 mph (48 km/h) impact with an immovable barrier (200 ton). Despite this, the British AA motoring association has described the car, like many other classic models, as much less safe than modern cars, and the issue received public attention following a 2013 case in which a driver in a hired 1963 MGB was killed in a collision with a taxi.

A limited production of 2,000 units of the RV8 was produced by Rover in the 1990s. Despite the similarity in appearance to the roadster, the RV8 had less than 5 percent parts interchangeability with the original car.