The Austin-Healey Sprite series AN5 (produced between 1958-1960) is the original Sprite. It is perhaps better known in North America as the Bugeye and elsewhere as the Frogeye. This nickname is owing to the unique headlight mounting. 48,987 examples were produced, making it the most numerous, by far, among all cars ever to bear the name Healey. Power was supplied by the Austin 948 cc A-Series engine producing 43 hp, and while performance was hardly neck snapping, no one complained because the car was just so much fun to drive.
In addition to the unusual headlight treatment, another design idiosyncrasy of the Bugeye is the lack of a boot lid, or exterior trunk opening. Instead, access to the boot was only through an opening behind the seats. There were also no outside door handles. All Bugeyes were roadsters fitted with side curtains (no roll-up windows on these cars), and so opening the door simply meant reaching inside, over the top of the door, to access the inside door handle.
Options were also few on this inexpensive model. In fact, the front bumper was an optional extra! Other commonly found options were a heater and a tonneau cover, but perhaps the most desirable option was the handsome factory-produced hardtop. Note that Bugeyes had no carpet—at least, not originally. Instead, the floors were covered by molded, color-coordinated ribbed rubber mats that are now extremely rare and can usually be found only on a very, very few exceptionally well-preserved examples.
The Sprite Mark II (1961-1964)
The Mark II was a clear styling departure from its rather quirky-looking predecessor. The headlights were moved to a more conventional location in the "wings" (fenders to us Yanks), and a boot lid (trunk lid) was added to make access to the boot more convenient. It is a handsome car, although certainly less striking.
There were two variants of the Mark II. The first was the Series HAN6 model which retained the same 948 cc engine as the Bugeye, although with three more horsepower (46 hp). 20,450 examples were produced. Then in late 1962, the Series HAN7 was introduced. Although identical in appearance, it had an important performance upgrade in the form of a 1098 cc engine that produced 56 hp, and the addition of front disc brakes to help handle the added power. 11,215 examples were produced. All Sprite Mark II models were roadsters, retaining side curtains and an easily detachable folding top.
Dubbed "Mark II" to differentiate it from the original Bugeye Sprite, which was only retroactively dubbed "Mark I," this Sprite had a nearly identical twin wearing the famous MG octagon: the MG Midget. Beginning with this model and continuing throughout the reminder of Sprite production (and beyond), the MG Midget was a slightly upscale badge-engineered counterpart. Curiously, while the Big Healey was a more expensive car than the MGA and MGB that were produced contemporaneously with it, the MG Midget was the more expensive, slightly upscale variant between the Midget and Sprite.
Because of the nearly identical nature of the Sprite and Midget, long ago someone created the name "Spridget" to denote the genre. This term stuck and is now used to describe all Sprites and Midgets combined.
The Sprite Mark III (1964-1966, Series HAN8)
The Mark III a transition model between the Mark II roadster that preceded it and the Mark IV convertible that followed it. While the Mark III had the roll-up windows of a "convertible," it still had the easily detachable, button-down soft top of a "roadster." It was a definite improvement in weather protection, but still not quite fully a convertible. Still the same handsome car as its Mark II predecessor, it retained the same 1098 cc engine as the Mark II Series HAN7, although with three more horsepower (59 hp). 25,905 examples were produced.
Sprite Mark IV (1966-1969 HAN9)
For practical purposes, the Austin-Healey Sprite Mark IV represents the final development of the line. This model was a true convertible, meaning that it had roll-up windows and a permanently attached folding top. The appearance hadn't changed, but this model possessed a 1275 cc engine that produced 65 hp. 20,357 examples were produced.
The Sprite Mark V (1969-1971, Series HAN10 and AAN10)
The Mark V is virtually unknown in the USA since it was never imported there. It is also virtually the same car as the Mark IV, but with very minor updates and produced only for the "Home Market" (the UK). Just 1411 examples were produced in its short production run. It was also followed by an Austin Sprite (no "Healey" in the name), produced in the first half of 1971 after British Leyland's contract to use the name "Healey" had run out. Only 1022 examples were produced.
These models represent the phase-out of the Sprite in favor of its twin brother the MG Midget, production of which continued through 1979. For practical purposes, the Sprite Mark V and Austin Sprite are the same car as the Sprite Mark IV.
Despite the high number of Sprites produced, strictly original examples are now somewhat difficult to find. Many Sprites have been used, hard, in club racing over the years, and consequently have been extensively modified and often significantly damaged and repaired, sometimes repeatedly. Beware a car with a racing history.
Engine swaps with later Sprites (to 1098 cc and 1275 cc engines) are also common, as are transmission swaps from those later models. However, these drivetrain swaps significantly upgrade the performance of the car without changing its heritage or character—after all, the later engines are merely further developments of the same Austin A-Series engine—and so few would object.
Note also that engine swaps are often accompanied by swaps to the front disc brakes that became available on later models. The original drum brakes were barely up to the task of stopping a 43-hp Bugeye, and those cars with drivetrain swaps and therefore more horsepower really benefit from the later, more efficient disc brakes.