Many Nissan enthusiasts regard it as a great loss that the Mid-4 concept of the late 1980’s never reached production, despite extensive development and some very favourable reviews in the media. However, the Mid-4 wasn’t Nissan’s only still-born mid engined sports car. A Decade earlier, in 1975, the Nissan AD-1 had gone on public show for the first time at the 21st Tokyo Motor Show. The AD-1 was a neatly styled, aerodynamic little two seater coupe with a mid mounted transverse engine, similar in layout to Toyota’s MR2 which wasn’t launched until some nine years later.
The AD-1 was styled with the help of wind tunnel research with a view to achieving the best aerodynamics possible, something they achieved admirably with a mere 0.26 Cd, remarkable even by todays standards. The low drag, allied to the low kerb weight of just 740kg, would have helped the car to give quite lively performance whilst still retaining a relatively small and economical engine.
In the AD-1 this was a 1.4 litre overhead valve A14 engine equipped with electronic fuel injection. Cooling the unit via long pipes to a small front mounted radiator meant the body sides could be kept free from unnecessary air intakes, whilst excess engine compartment heat was vented through grilles in the engine compartment cover behind the rear window. The AD-1 was also equipped with a 5 speed gearbox. Underneath the car was suspended by McPherson struts all round and featured duel circuit, four wheel disc brakes. Whilst today the technical details of the chassis might not seem adventurous, it was quite high specification for a small Japanese car in 1975.