1978 MG Midget MK IV

The MG Midget two-seater sports car was produced from June of 1961 to 1979 and were essentially a badge-engineered and slightly more expensive version of the Austin-Healey Sprite MK II. Distinguishable differences were in the grille design, interior trim, instrumentation, and badging, and the Midget gained external polished trim.

Both the MG and Austin-Healey shared mechanical components including the quarter-elliptic leaf springs in the rear and trailing arms. The 948cc A-Series engine was equipped with twin SU carburetors and produced 46 horsepower and 53 lb-ft of torque. The brake drums measured 7-inches and were installed in the front and the rear. Factory options included a radio, heater, luggage rack, and a hardtop.

Engine displacement grew to 1098cc in October of 1962 and output rose to 56 hp at 5,500 RPM and 62 lb-ft at 3,250 RPM. The prior front drum brakes were replaced by discs, and 13x4 wire-spoke wheels joined the optional equipment list.

The MG Midget MkIII, built from 1966 to 1974, had numerous improvements to its engine, including a larger 1275cc displacement size, 12G940 cylinder head casting, an 8.8:1 compression ratio, and 65 horsepower at 6,200 RPM. Its torque was rated at 72 lb-ft at 3,000 RPM. This was the engine used in the Mini Cooper 'S', but the Mini had a higher compression ratio of 9.75:1, special heads, larger inlet and exhaust valves, and produced 76 horsepower. Another update applied to the MKIII was a permanently attached hood with an improved opening mechanism.

During its production lifecycle, the MKIII's built for the United States received safety improvements that included a third windshield wiper, anti-burst door latches, a padded dashboard fascia with smaller main gauges, scissor-type hood hinges, a collapsible steering column, and additional side marker lights. In August of 1971, the compression ratio on U.S-spec engines was reduced to 8.0:1 and engine output decreased to 54.5 bhp and 67 lb-ft at 3,250 RPM.

Minor updates were made to the exterior in late 1969 for the 1970 model year, with the sills painted black, squared-off taillights, and a revised recessed black grille. The 13-inch Rubery Owen 'Rostyle' wheels became standard while the wire-spoke units joined the options list. A few cars had matt black-painted windscreen surrounds, but after consumer complaints, the Midget reverted to the original brushed alloy.

Rounded rear wheel arches replaced the previous square-shaped units in January of 1972, and a Triumph steering rack and a second exhaust silencer were added later in the year. Alternators replaced the dynamos in 1973. Complying with U.S. bumper impact regulations, oversized rubber bumper blocks were added to the chrome bumpers in mid-1974.

A total of 77,831 examples of the MG Midget MkIII were produced.

The MG Midget 1500 was built from 1974 to 1980 with 73,899 examples built. As safety and emissions gained higher priority in the late 1960s, followed by fuel shortages in the early 1970s, new U.S federal regulations were introduced resulting in drastic changes throughout the industry. MG complied by adding large black plastic-covered bumpers and increased the ride height. Engineers fitted anti-roll bars to help cope with the higher center of gravity and to improve handling. A 1493cc Standard SC engine replaced the previous A-Series unit and was backed by a modified Morris Marina gearbox with synchromesh on all four gears. The engine was better suited to meeting emission regulations, but added air pumps, EGR valves, and catalytic converters robbed it of its performance. In 1976, the dual SU Hs2 carburetors installed on U.S.-spec cars were replaced by a single Zenith-Stromberg 150 CD4 unit catalytic converter carburetor. Square rear wheel arches returned and added rigidity to the body, and the front wheel arches were lowered.

By Daniel Vaughan | Jul 2010