ASC One of a Kind:
Special Built Nissan 300ZX (Retractable Hardtop)

identification Nissan 300ZX by ASC
year 1991
vin number JN1RZ26H4MX500006
country Japan & USA
appearances Geneva Auto Show on March 3, 1992
body 2-door 4-seat coupe / convertible / electric retractable hardtop
designer Darin Kirschner
engine front-mounted v6 / 2960cc / double overhead camshaft / 24 valves / electronic injection
transmission rear wheel drive
suspension independent wheels / coil springs / anti-roll bars
brakes power ventilated discs / abs
steering power rack and pinion
wheels one-off 17-inch polished aluminum wheels
dimensions wheelbase 257 cm / length 452 cm / width 180 cm
performances 222 horsepower / 5-speed manual transmission
production 1

The 1991 Nissan 300ZX hardtop convertible was custom built for the 1992 Geneva Auto Show by ASC as a possible production-ready version of a 300ZX convertible. Of course, you know that Nissan never built a hardtop convertible, instead preferring to go with a traditional folding cloth top, but the story doesn't end there. Read on to find out more.

l'auto-journal prestige (issue 8 / 1992)
The American Sunroof Corporation (ASC) has been building convertibles for OEM applications for years, and when the new 300ZX came out, they knew it would only be a matter of time before Nissan would want to market a drop-top version. Introduced at the Geneva Auto Show on March 3, 1992, this Nissan 300ZX convertible with a retractable hardtop was built to highlight the ASC articulating hardtop technology in a fully functional sports vehicle. The challenge in building this vehicle came in retaining the full-width rear seat, which they managed to do, giving this car room for 4. The car features an all-metal folding hardtop that retracts and folds into the rear storage area with the touch of a single button.

autoscope (tuning special issue / 1992)
The key words with this important car are "all-steel" and "OEM". ASC built this car as a proposal to Nissan for a convertible 300ZX, and as such, it is built to original equipment manufacturer (OEM) standards. This is not a one-off custom by some chop shop; this is a 100% production-ready prototype built by the company that builds convertibles for some of the world's largest automakers. Because of this, every single part has been designed and built with OEM tolerances and finishes, with reliability and functionality on par with anything you would buy at a new car dealer. There are no cobbled-together bits from other convertibles on this Z; this is a fully-engineered hardtop convertible (the first since the Ford Retractable in 1959) with full weather seals, finished upholstery, and no compromises. The rear window defroster works, the rear quarter windows are power actuated, and the rear seats are completely usable.

It's also important to note that this car is all steel. No fiberglass was used in the construction. On a project like this, fiberglass would be the obvious choice for its ease of fabrication and the ability to make complex shapes. However, as an OEM supplier, ASC knew they needed to design and build a system that would not only look great, but that would meet OEM standards for fit, finish and production feasibility. That meant steel. As a result, this car is incredibly solid and the workmanship is first-rate. Kudos to the craftsmen at ASC for making it not only functional, but attractive too. Given all the research and development that went into designing this car, not to mention the labor to actually build it, the cost on the project was more than three-quarters of a million dollars! Yes, you read that correctly—this car cost nearly $800,000 to build in 1992.

autoscope (tuning special issue / 1992)
The car itself is a stock 4-seater 1991 300ZX with a naturally aspirated 3.0 liter V6 making 222 horsepower and tied to a 5-speed manual transmission. It maintains all the original car's features and amenities including power windows, power locks, power seats, 4-wheel disc brakes with ABS, A/C and a powerful AM/FM/CD stereo system with a touch screen interface. It rolls on a set of one-off 17-inch polished aluminum wheels with 245/40/17 ultra-high-performance tires.

l'auto-journal prestige (issue 8 / 1992)
For the show, the car was painted in a custom color called Mayorka Green Pearl, which is sophisticated and very light-dependent. Under some conditions, it looks almost blue, but in bright sunlight, it's a lovely turquoise. The 100% custom interior is ivory-colored leather with black accents.

So whatever happened to the ASC retractable hardtop program? I know I promised you the rest of the story, and it doesn't end with this car. Although Nissan passed on this project and ultimately went on to produce a cloth-topped 2-seat 300ZX convertible, the idea of a retractable hardtop was immensely appealing to another high-tech Japanese automaker who was bringing an equally potent performance car to the market. That company is Mitsubishi, and the car became the 3000GT Spyder. So the investment and prototype work that went into making this 300ZX an OEM-grade convertible was not for nothing, as Mitsubishi put the ASC system into production in 1995.