The history of the MG Midget can be better explained in the History section of the MG Midget Registry webpage from which the following is an excerpt:
“The first ‘modern’ Midget was essentially a re-badged Austin Healey Sprite MkII which itself was a development from the the original 1958 MkI Sprite, more frequently known as the Frogeye. The name ‘Midget’ was first used by MG in 1929 ascribed to the M Type, this being MG’s first baby sports car based on the then newly released Morris Minor. Rapid development of the overhead cam sports and racing cars through the early 1930’s led to subsequent C ,D, J, P, Q, and R type Midgets, this being MG’s most exciting period. Then came the first of the T Type Midgets the TA in late 1936, culminating with the TF model of 1954. When the TF’s successor, the MGA, was being planned, it was considered the car had by now grown too large to be referred to as a Midget any longer, and so the name was dropped, not being revised until the new semi-monocoque car was launched in 1961.
In 1966 yet more power was available by the fitting of the 1275cc 64bhp version of the ‘A’ series engine, unfortunately though not the full 75bhp Cooper ‘S’ version. This model, the MkIII, also benefited from a superb new design of folding hood, and a larger fuel tank. It was at this point however that all further mechanical development of the model sadly came to a halt, it remaining largely unaltered until 1974, although from the Leyland take-over in 1968 there were minor annual styling updates, mostly irrelevant, starting with the application of much matt black paint, a change in bumper design and rear light clusters, ‘mag’ style Rostyle wheels fitted as standard, and a new pattern of seat material in late 1969. In 1970 the Austin Healey Sprite model became just an Austin Sprite, which the following year after just 1022 had been made was dropped altogether. By this time however the two models had become identical in all but badge. Come 1972 and a slightly more notable alteration was made, when rounded rear wheelarches were introduced, a design cue not seen since the original Mark I Frogeye Sprite. Also at this time Rostyle wheels, similar to those fitted to MGB’s were fitted as standard with wires still being offered as an option, and all the interior switches were made to be of the rocker type in the aid of safety. In late 1974 however the car underwent its final and most significant change, for to keep the model in line with the ever increasing safety and emission rules being introduced in the US, heavy energy absorbing bumpers were fitted along with a 1498cc 65bhp engine from the Triumph Spitfire. This engine was chosen as it had previously passed all US emission specification requirements, and it was unlikely the ‘A’ series would without serious development. This Triumph engine was mated to a fully synchromesh gearbox taken from the Morris Marina range.
Marginally more powerful, this final version could in standard form just reach 100mph, something non of the previous standard cars could achieve, although it took a while to get there. Its appearance due to the bumpers was considerably altered, the Midget 1500 also featuring a return to the square design of rear wheel arch. In 1976 wire wheels were dropped from the option list. The car then continued in this guise with just slight annual cosmetic revisions until 1979 when production finally ceased on December 7th.”