Throughout the production run, several special edition models were launched. Customers who chose a Calibra Cliff Motorsport Edition in May 1996 were way ahead of the game. Its paintwork was the same as the Class 1 racing car in which Manuel Reuter would win the ITC championship for Opel at the end of the season. The street-legal Cliff racer had a 20 mm lower sports chassis and BBS light alloy wheels (7J x 16).
In July 1990, after General Motors bought a stake in Saab, it was reported the Calibra would be badged as a Saab in the United States, but these plans did not materialise. There were also plans for a cabriolet version to be produced, but these too failed to materialise, although Valmet Automotive built two fully working, red coloured prototypes in 1992, with the 2.0 litre, 8 valve engine.
A third body was also produced for use in flexibility tests. In the summer of 1994, the Calibra received a light facelift. Most noticeably, the manufacturer badge migrated from its place atop the leading edge of the bonnet into the front grille. Throughout the production run, several special models were launched. In the United Kingdom, this began with the 'Tickford' conversion in October 1991, however only 26 Calibra's were ever converted.
The extra-light, all-aluminium engines, together with optimization of the front and rear axles, also contribute to the low total weight. The particularly compact three-cylinder petrol engines weigh around 15kg less than the previous generation of similarly powerful four-cylinder units. Highly unusual in the small-car-sector is the new Corsa’s aluminium engine bonnet, which although longer, saves 2.4kg in comparison to the previous model’s bonnet made of steel. The Insignia flagship was previously the only model in the Opel range with an aluminium bonnet. The seats also have been put on a diet. The new optimized seat structure saves a total of 10kg – 5.5kg at the front, 4.5kg at the rear. New lighter insulating material was used for fine tuning. Altogether the measures result in a weight reduction that, in combination with optimum aerodynamics and the efficient powertrains, will lead to a considerable reduction in fuel consumption and CO2 emissions.
The manufacturer now offered two versions of the Kadett, designated the "Kadett KJ38 and the "Kadett K38" the latter also being sold as the "Kadett Spezial". Mechanically and in terms of published performance there was little to differentiate the two, but the "Spezial" had a chrome stripe below the window line, and extra external body trim in other areas such as on the front grill. The interior of the "Spezial" was also better equipped. To the extent that the 300 Mark saving for buyers of the car reflected reduced production costs, the major difference was that the more basic "KJ38" lost the synchromous springing with which the car had been launched, and which continued to be fitted on the "Spezial". The base car instead reverted to traditional rigid axle based suspension similar to that fitted on the old Opel P4.
The Kadett clearly featurt a muckle mair modren design than the Volkswagen Beetle which then dominatit the mercat for smaw family caurs in Germany an various surroondin kintras. The Kadett affered mair passenger space, massively mair luggage space an a muckle less encumbered view oot. Its watter cooled ingine enabled it tae provide a far mair effective heater. Even fuel consumption wis unner maist conditions superior tae that o the Volkswagen, an mony commentators muckle preferred the Opel's handlin an its licht an effective brakes tae those o the mercat leader.
This range of engines was also used for later models of the Corsa/Nova, and the mid-sized Cavalier/Ascona. From May 1981, the 1.3 was also available with a three-speed automatic. The automatic was made available to the diesel in September 1982. One interesting version which first appeared in mid-1982 was the Kadett Pirsch, (for deer stalking, a stealthy form of hunting). In non-German-speaking countries it was generally marketed as the Kadett Off Road. This was a station wagon with rustic trim, fitted with a differential brake, reinforced suspension and more suitable tires, increased ground clearance, a skid plate, and shortened front fenders. In Sweden, a special postal Kadett ("Opel Kadett Post") was offered, fitted with a high roof (necessitating a unique and much taller windshield) and a sliding right-hand door, RHD, and the automatic transmission. This version was converted by Karosseriefabrik Voll (in German) in Würzburg, Germany. Voll also made a postal version of the Kadett E.
The Kadett C appeared in August 1973 and was Opel's version of the General Motors' "T-Car". It was the last small Opel to feature rear-wheel drive, and remained in production at Opel's Bochum plant until July 1979, by which time Opel had produced 1,701,076. Of these, 52% had been exported outside West Germany, most of them to markets in other parts of western Europe.
One of the most versatile small German military vehicles, the Kettenkrad, a blend of a tractor and a motorcycle, was powered with a 1.4 L Olympia four-cylinder engine. Produced by NSU, it had motorcycle-type front-wheel steering for gentle turns and negotiated tight corners with brakes on the propelling caterpillar tracks. The Kettenkrad towed antitank guns and transported troops and signal gear in several theatres of war. NSU continued to make it after the war for use in mines and forests. It was one of the few vehicles that could do jobs formerly performed by horses for which, owing to the shortage of oats, even less fuel was available than for motor vehicles.
Vega appears to have been the first GM vehicle designed by committee – the corporate engineering staff – and imposed upon one of its divisions like a turd to be polished. Chevrolet engineering had in fact developed its own subcompact but when presented to corporate it was rejected “out of hand” by Ed Cole, who told them to develop Vega instead, then code-named “XP-887”.
During its lifetime, the Calibra was much more popular in Europe, and outsold its nearest rival, the Ford Probe, which was considered to be underpowered, and very American for most European drivers. However, in the United Kingdom, it failed to outsell the Rover 200 Coupé, which offered comparable performance, but without 4WD in the top of the range models.
The Kadett A (above) finally appeared in 1962, and was a classic GM/Opel effort: highly pragmatic, conventional in every respect, reasonably stylish for its time, and designed to deliver a good bang for the buck. In just about every way possible, it was the antithesis of the VW: front-engine rwd, a rather tinny but roomy body, highly tossable but with a primitive suspension and ride, a very roomy trunk, and excellent visibility as well as economy. Oh, and a proper heater even! Its little 987 cc OHV four made 40 net/46 gross hp, six more than the VW 1200. Its trim fighting weight of 1475 lbs (670 kg), some two hundred pounds less than the VW, showed in both its acceleration and body integrity.