In 1965, the Prince Motor Company launched its racing car, named Prince R380. The car was designed to contend in the Japanese Grand Prix. In 1966, a merger between Nissan Motors and Prince Motor Company took place that resulted in the production of R380-II (also R380 Mk-II) that was derived from the R380.
In the second Japanese Grand Prix held in 1964, Prince Motor took part with their new S54 Skyline GTs. With a new G-7 Straight-6 engine, the company hoped to demonstrate the performance potential of the car. Despite its good performance, it was defeated by Porsche 904GTS.
Prince Motor Company soon realized the vitality of the mid-engine layout that was used in the Porsche 904. Hence, Prince became conscious of the fact that there would be no way to win Grand Prix without a custom-built car. Prince Motor Company manufactured a car from scrape that featured an all-new chassis to accommodate the engine in the middle. Aerodynamic bodywork with exposed buttresses was also used above the rear engine cover.
As for engine, the G engine used in Skyline was opted with little modifications for the R380. The altered engine was given the name GR-8, straight-6 with an engine displacement of 1996 cc. it delivered 200 hp (150 kW). The engine was mated to a Hewland 5-speed racing gearbox.
After the merger of Prince Motor Company with Nissan Motors, the bodywork of R380 was completely revised, i.e. the rear buttresses were withdrawn in favor of a flowing cockpit and engine cover, whereas the vents and ductwork were refurbished.
The Japanese Grand Prix was called off for the year 1965 as a result of which Prince started utilizing the R380 to test the high speed aerodynamics. This eventually enabled the car to break five E-class land speed records in later half of 1965.
As for 1996 Japanese Grand Prix, Prince raced with four R380s, while Porsche entered with its trio of new Porsche 906s. R380 came out to be the winner in that Grand Prix with Yoshikazu Sunako’s R380 remained on the top with Hideo Oishi’s R380 ended up in second place.
Once Nissan took the authority to rebuild the R380, four R380s were entered in the Japanese Grand Prix for another time. However, this time Porsche 906s took the lead and won the title by the difference of 2 minutes, while the R380s secured second, third, fourth and sixth place. In later years, Nissan R380-II set new land speed records and broke seven records in just one year.
In 1968, Nissan introduced a newer version called the R381. The sales of the R380 were then limited to the privateers. Three of the new R381 once again entered in the Japanese Grand Prix and stood third, fourth and fifth. In the 1969 Chevron Paradise 6 Hour race at the Surfers Paradise International Raceway in Australia, Two Factory entered with R380s which took first and second places. R380 continued to perform well in races as it took second place in the 1000 km of Fuji race in 1969 followed by another second place victory an year later in 200 mile (320 km) race at Fuji.
Nismo restored an R380-II vehicle in 2005 and displayed it in many events with certain other vehicles of its series.