The Z32 discontinued sales in 1998 because Nissan was begining to go bankrupt. They could not afford to sell the Z32 in the States anylonger due to the fact that they were just not selling. And for those of you who don't know Renault bought/merged (not sure which) with Nissan late in 1998. Renault had NO intention of continuing the Production of ANY Z, but the sales were good enough in Japan to continue selling the Z32 for a few more years. After the end of production of the Z32 there was not going to be a new Z....In comes the gorilla team of designers who worked off the clock and late at night to create the Z33. Nissan then showed it as a prototype to see how much appeal it made to the general public....and I'm sure you know the rest.
Actually if I remember corectly, the Z32 came out in June of 89 as a 90 model year. I tried to buy one in October 89 and it was a 90 model year I test drove. They would only give me 4000 in trade on my 85 Turbo so I kept it and bought the 93 Z32 in 1996. Still got both.