The considerable worldwide success of the MGA brought about an even more refined and modern model that was designed in-house at MG and was introduced in 1962 at the Earls Court Motor Show. Known as the MG 'MGB', it had monocoque construction, a tried-and-true B series four-cylinder engine, and a smaller overall footprint yet with increased interior space and more legroom. With twin SU carburetors, the engine offered 94 horsepower at 5,440 RPM and was paired to a four-speed gearbox, endowing the MGB with a zero-to-sixty mph time of 11.4 seconds. The suspension was carried over, comprised of an independent setup at the front with coil spring wishbones, while the rear had a live axle with leaf springs. Disc brakes were at the front and drums were at the rear.
A host of changes arrived in late 1967, prompting the factory to define a new 'Mark II' model. Updates included synchromesh on all 4 gears with revised ratios, an optional Borg-Warner automatic gearbox, a new rear axle, and an alternator in place of the dynamo with a change to a negative earth system. Numerous significant changes were required to accommodate the new gearboxes, including updates to the sheet metal in the floor pan and a new flat-topped transmission tunnel.
Initially, the MGB was offered solely as a roadster and was joined in October of 1965 by a fixed-roof 'GT' model. This 'coupe' body style was produced through 1980, although export to the United States ended in 1974. The sporty 'hatchback' styling added additional weight compared to the roadster, resulting in slower acceleration, but its improvements to aerodynamics increased its top speed by 5 mph to 105 mph. Pininfarina had been tasked with creating the hatchback styling, giving it a different windscreen that sloped slightly to the sides with a gentle rearward rake, integrated into a sloping roofline that continued rearward into the hatchback. The design allowed for adequate headroom required for 2+2 seating and offered more luggage space than in the roadster.
Both the roadster and the 2+2 GT Coupe rested on a 91-inch wheelbase and measured 153 inches in length. The addition of mandatory rubber bumpers years later increased the overall length to 158.2 inches.
Power was from the 1.8 liter (1798cc) B-Series engine with a five-bearing crankshaft and delivering 95 horsepower at 5,400 RPM. There was a four-speed manual transmission with overdrive and Lockheed disc brakes up front. While many of the mechanical components remained the same as the roadster, the GT gained revised suspension settings including stiffer springs, an anti-roll bar up front and a Salisbury-type back axle.
Like the roadster, the MGB GT was technically more advanced than the MGA and more civilized, with wind-up windows and door locks. It successfully combined attractive styling and lively performance with great value, enabling BMC to dominate the affordable sports car market around the world throughout the 1960s. It outsold its rivals such as the Triumph TR, and the addition of the fixed-head coupe variant with occasional rear seats and a snug weatherproof cabin vastly increased its appeal.
by Dan Vaughan