Nissan Skyline R31 (1985–1989)

How the R31 moved on from the R30

The R30 had relied on four-cylinder engines for its sporting image, including the FJ20 twin-cam. The R31 switched the focus back to six cylinders. Its new RB engines were straight sixes with belt-driven camshafts, a cast-iron block and an aluminium head. English Wikipedia notes that the 2.0-litre RB20 shares its bore and stroke with the older L20 six, which it replaced.

The body grew slightly larger and squarer, on a platform loosely based on the C32 Laurel. The five-door liftback of the R30 was not continued, but a four-door pillarless hardtop, usually badged Passage GT, joined the saloon. It is the only Skyline sold with this body style. A two-door coupé and an estate were added in 1986. In Japan, owners nicknamed the car "Seventhsu", after its position as the seventh Skyline.

Our Nissan Skyline history covers all 13 generations, from the 1957 Prince Skyline to the V37.

Passage hardtop, GTS coupé and estate

Japanese R31 production began in the summer of 1985 at Nissan's Musashimurayama plant: English Wikipedia gives July, German Wikipedia August. The sporting GTS coupés arrived in May 1986, and in August 1987 the saloons adopted the coupé's front end. The estate was a practical choice for families and is now one of the rarer bodies; similar load carriers can be found among our station wagons.

Dimensions changed with the facelift. English Wikipedia lists the early saloon and estate at 4,590 mm (180.7 in) long and the early hardtop at 4,650 mm (183.1 in), while the coupé and the facelifted four-door models measured 4,660 mm (183.5 in).

RB20, RD28 and CA18 engines

The table shows the main Japanese engines. Many were rated in JIS gross terms, so outputs are given as kW followed by the PS figure from the source.

The early twin-cam engines used NICS induction with twelve small intake runners. Later versions switched to ECCS management, six larger runners and a bigger turbocharger. Their red cam covers gave them the "Red Top" nickname among owners.

HICAS: rear-wheel steering arrives

HICAS stands for High Capacity Actively Controlled Steering. Nissan showed it on the MID4 concept in 1985, and Wikipedia's HICAS article places its first production use on the R31 GTS coupés in 1986. The system was simple by later standards. Above 30 km/h (19 mph), hydraulic pressure from the power-steering pump moved the rear wheels by up to 0.5 degrees in the same direction as the fronts, by compressing the rear suspension bushes.

The aim was stability during fast lane changes rather than easier parking. Later versions, including Super HICAS on the R32, added counter-steering phases and electronic control.

GTS-R: the Group A homologation coupé

The HR31 GTS-R coupé was introduced in October 1987. It had a reworked RB20DET-R with a much larger turbocharger on a tubular steel manifold, a larger front-mounted intercooler and a bigger rear spoiler. English Wikipedia says 823 were built; German Wikipedia and the RB engine article give about 800.

In Group A form the engine produced more than 316 kW (430 PS), but the car was still at least 81 kW (110 PS) down on the Ford Sierra RS500. It nevertheless won. Jim Richards and Mark Skaife took the 1989 Sandown 500 in a Gibson Motorsport GTS-R, and Richards used the car in six of the eight rounds of the 1990 Australian Touring Car Championship, switching to the R32 GT-R only for the last two. That title was Nissan's first in the series.

R31 coupé dimensions and weights

German Wikipedia gives these figures, which match the coupé in English Wikipedia.

German Wikipedia gives a top speed of about 200 km/h (124 mph) for the RB20DET turbo.

Australian and South African R31s

Nissan Australia built the R31 at Clayton from 1986 to the end of 1990, as a saloon or estate with a locally fitted 3.0-litre RB30E six. Emissions rules cut its output to 114 kW (155 PS) and 247 Nm (182 lb-ft), and the Silhouette GTS1 and GTS2 versions raised that to 130 kW (177 PS) and 140 kW (190 PS). A four-cylinder sister car with a 2.0-litre CA20E was sold as the Nissan Pintara.

In South Africa, about 29,305 R31 saloons were built between 1987 and 1992, with RB30E, RB20E or four-cylinder engines. They were the last Skylines sold there. The R31 was also offered in Kuwait and Oman with RB30 sixes.

Crash-test status and active safety

The R31 was designed long before independent crash testing in Europe or Japan, and we found no crash-test result for it. Its contribution to active safety was HICAS, which aimed to keep the car stable during sudden steering inputs. Seat belts and the braking system are the main points to check on any car of this age before relying on it.

Which R31 to look for

Japanese imports, Australian RB30 cars and a few South African saloons all appear on the classic market, so the market of origin matters.

• GTS-R coupé (1987): the homologation special with 154 kW (210 PS), the most collectable R31.
• GTS Autech: an Autech-developed version that shares the GTS-R engine and its 154 kW (210 PS) rating.
• GTS Turbo and GTS-X coupé: RB20DET with 132 or 140 kW (180 or 190 PS) and, on many cars, HICAS.
• GT Passage hardtop: the unique pillarless four-door, often with the RB20 or diesel engines.
• Australian Silhouette GTS2: the most powerful local RB30E version.

Rivals of the period included the Toyota Supra, and the Nissan catalogue lists the later Skylines and other models. More background is in the history of Nissan.