The Porsche 959 was Nissan's target when designing the GT-R. The chief engineer, Naganori Itoh, intended to use the car for Group A racing, so the design specification was drawn up in conjunction with a copy of the Group A rules. The Nordschleife production car record at the time of development was 8'45" - set by a Porsche 944. Nissan test driver Hiroyoshi Katoh reset the record with a time of 8'20".[11] Best Motoring managed 8'22"38

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