The fixed-roof MGB GT was introduced in October 1965. Production continued until 1980, although export to the US ceased in 1974. The MGB GT sported a ground-breaking greenhouse designed by Pininfarina and launched the sporty "hatchback" style. By combining the sloping rear window with the rear deck lid, the B GT offered the utility of a station wagon while retaining the style and shape of a coupe. This new configuration was a 2+2 design with a right-angled rear bench seat and far more luggage space than in the roadster. Relatively few components differed, although the MGB GT did receive different suspension springs and anti-roll bars and a different windscreen which was more easily and inexpensively serviceable.
Although acceleration of the GT was slightly slower than that of the roadster, owing to its increased weight, top speed improved by 5 mph (8.0 km/h) to 105 mph (169 km/h) because of better aerodynamics.
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.