Nissan R390 GT1

After returning to sports car racing in 1995, Nismo (Nissan motorsport) had some measure of success with their Skyline GT-R LM which had competed in the GT1 class. However, these cars were quickly outpaced by the influx of new manufacturers who were using loopholes in the GT regulations to build racing cars that bore little resemblance to their GT1 class competitors, examples being the Mercedes-Benz CLK GTR and the Porsche 911 GT1. Nismo's Skyline GT-R therefore needed to be replaced with a purpose built racing car. Turning to Tom Walkinshaw Racing (TWR), Nismo began developing a prototype of the R390 GT1, named to follow in the tradition started in the 1960s with Nissan's R380. The first decision for Nismo and TWR was the choice of engine. The previous Skyline GT-R LM had used the trusted RB26DETT Inline-six engine, but the design was old for a racing car, employing an iron block which added weight and had a high center of gravity. Nismo instead chose to resurrect an engine from the Nissan R89C, a racing car from the Group C era. Its powerplant, the VRH35Z, was a V8 engine which used an aluminium block, as well as having a lower center of gravity and a better ability to be used as a stressed member over the RB26. Thus the engine was modified and designated VRH35L and would produce approximately at 7,000 rpm. For the road going version, the engine was detuned to . The car's styling group was led by Ian Callum of TWR. The mechanical and aerodynamic design was led both by Tony Southgate, also of TWR, and Yutaka Hagiwara of Nismo. Southgate was the designer of the Jaguar XJR-9 amongst other TWR sports cars, which had won at Le Mans. Due to this, the R390 GT1 bears a resemblance to the Jaguar XJR-15, which was also developed by TWR and based on the XJR-9, and in fact used a cockpit - including the tub, greenhouse and roof line - from the very same tooling as the XJR-15, with some custom tooling blocks added to the XJR15 chassis mold, although for the R390, the rear and front ends, and suspension were completely different and were designed to meet GT1 specifications, the R390's chassis was lower and wider, but slightly shorter in length than the Jaguar, making the R390 larger overall. Development of the car was achieved in a small amount of time, especially due to the use of an existing engine. Nismo and TWR also had to build a road legal version of the R390 GT1 in order to meet homologation requirements. A red R390 prototype underwent wind tunnel testing and aerodynamic improvements in England, however, the final car was built and tested in Atsugi, Japan. Only one road legal R390 was built, which is currently in storage at Nissan's Zama, Kanagawa facility. After all three cars failed scrutineering at the 1997 event, they had to be modified in order to be allowed to race. This subsequently led to overheating problems for the gearbox, and ultimately led to their failure during the race. That is why for 1998, the R390 was modified, most notably in the extension of its rear bodywork to create increased "luggage space" in order to satisfy the ACO, a new rear wing for racing models (the road legal version had no wing), and a rear diffuser for improved downforce were added. ==Racing results==

. Completed in time for the 1997 24 Hours of Le Mans, the three cars were painted in a black and red livery. In their first outing, pre-qualifying in May, Martin Brundle archeived the fastest time of the field with 3.43.15. At the race itself, the best R390 GT1 (#22) was able to qualify in 4th on the grid and 2nd in its class behind a Porsche 911 GT1, while the other two cars qualified 12th (#21) and 21st (#23). During the race the cars were competitive, but soon began to struggle with gearbox problems and, around halfway through the race, two of the three cars (#21 & #22) finally succumbed to mechanical failure and were withdrawn. The third R390 survived the rest of the race (albeit with two complete gearbox changes along the way) finishing 12th overall and 5th in class, Following the 1998 24 Hours of Le Mans, rules for the GT classes were changed, mostly to end the number of manufacturers attempting to use loopholes. Instead of LMGT1, an LMGTP prototype class for closed cockpit cars was introduced for the 1999 Le Mans 24h that allowed more race specific construction without any road-going considerations. With Mercedes and Toyota going to improve their already faster GTs, Nissan was forced to either modify the R390 to a prototype GT, or abandon it like Porsche did with the GT1. Nissan instead turned to the open cockpit LMP classes, developing the R391 prototype for 1999 with European collaboration. After mixed results, that included a win over Toyota in Fuji, this program would also be short lived. Nissan discontinued Le Mans style racing at the end of 1999. A total of eight R390 GT1 race chassis were built over the two years of the program. ==Road car==

Only one R390 road car was ever produced by Nissan as a prototype for the development of the race-cars and was never intended for sale, although Nissan did offer to build further versions at a value of US$1 million. The lone R390 GT1 is currently stored at Nissan Heritage Collection, along with the #32 R390 GT1 race car from 1998. The vehicle is powered by the same twin-turbocharged VRH35L V8 engine as the race car, generating a power output of at 6,800 rpm and of torque at 4,400 rpm (although Nissan claimed lower figures of "over " at 5,200rpm and "over " of torque at 4,000 rpm). All of this power is sent to the rear wheels via a six-speed sequential manual transmission. The car is able to accelerate from in 3.9 seconds and complete the quarter-mile in 11.9 seconds. ==Appearances==

Both R390 GT1 race and road cars were featured as a playable vehicle in multiple video games such as Gran Turismo, Forza, GRID, The Crew 2, Project Gotham Racing, Real Racing 3, and Asphalt Legends. ==References==