Sport Prinz was initially powered by the Prinz 50 straight-twin engine but a maximum speed of was nevertheless claimed. From late 1962 a engine was fitted. The NSU Spider was a Wankel rotary powered two-seater roadster based on the Sport Prinz platform. NSU Prinz 4 One of the revelations of the Frankfurt Motor Show in September 1961, the Prinz 4 replaced the original Prinz. Its new body closely resembled the then fashionable Chevrolet Corvair, but was of course much smaller. Like the original Prinz, it was powered by a two-cylinder air-cooled engine in the rear. The Prinz 4 was much improved and continued to be a well-engineered car, like its predecessors. The engine carried on the tradition of eccentric rod driven camshaft inherited from NSU motorcycle engines and had a dynastart (combined starter/generator) built into the crankcase. The dynastart also works as a flywheel of the engine. Later four-cylinder engines adopted the more conventional (pre-engaged) separate starter motor and alternator. In 1968, Britain's Autocar road tested a Super Prinz. They had tested a Prinz 4 in 1962, and in commenting on how little the car had changed in the intervening six years quipped some of their road testers appeared to have gained more weight than the commendably light-weight Prinz in that period. The test car achieved a top speed of and accelerated to in 35.7 seconds. The home grown Mini 850 reached in 29.5 seconds in an equivalent recent test and also managed to beat the NSU's top speed, albeit only by about 3%. At this time, the UK car market was heavily protected by tariffs, and the Prinz's UK manufacturer's recommended retail price was £597, which was more than the (possibly below cost) £561 asked for the 850 cc Mini, but certainly not completely out of touch with it. The testers concluded their report that the car was competitively priced in its class and performed adequately. They opined, cautiously, it offered 'no more than the rest' but neither did it 'lack anything important'. Prinz 1000, TT The NSU Prinz evolved into the somewhat larger bodied NSU Prinz 1000 (Typ 67a), introduced at the 1963 Frankfurt Motor Show. A sporting NSU 1000 TT (with a 1.1 litre engine) also appeared, which was later developed into the NSU (1200) TT and NSU TTS models. All had the same body with inline-four air-cooled OHC engines and were frequently driven as sports cars,