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This article was first published in 2001.
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Of all the turbocharged cars sold new in Australia, the R32 Nissan Skyline GT-R is arguably the one that has had the most impact. Totally dominant on the track in Touring Car racing (until the rules were altered to ban it), the winner of contemporary handling comparisons against the very best from Europe and Australia, and with scorching straightline performance, the heavy-weight hitter catapulted turbo technology into the forefront of early Nineties performance.
Prior to the GT-R, many people viewed turbos more as a performance band-aid for small cars; after the GT-R exploded onto the scene, that view was gone forever.
Most unusually for a Japanese car, the Skyline followed a long history of high performance cars of the same name, with the nameplate actually extending back as far as 1957.
Older Skylines
"...the average buyer will get in [to the Prince GTB] and think it is a semi-competition machine, but an experienced racing driver will get in and think it's a GT with race potential." (Sports Car Road Tests Number Four)
Originally built by the Prince Motor Company, the very first Skyline was launched in 1957. It used a 4-cylinder, 1.5 litre engine and, as with most Japanese cars of the time, was awkwardly styled along vaguely English lines. But the Skyline name had been born.
In 1965, just before the Prince company was taken over by Nissan, a new S54 model Skyline was released. It featured a nose lengthened by 20cm to allow the fitting of a 2-litre six-cylinder engine in place of the normal four-cylinder. In its ultimate GTB 2000 development, this car was - in every respect - a very worthy predecessor to the modern GT-R.
The engine in the GTB was a highly-tuned version of the overhead cam two-litre G7 six, featuring a high compression and with three Weber 40DCOE-18 carbies bolted to the side. Developing 95kW (SAE) at 5600 rpm and 167Nm at 4400 rpm, it screamed up to its 6500 rpm redline in the first four gears of its close-ratio 5-speed. Power was transmitted to the ground through a factory 4.444 LSD, and a fuel tank of nearly 90 litres capacity meant that pit stops could be kept to a minimum!
Measured performance included a 0-97 km/h time of 10.1 seconds and a top speed of over 190 km/h. Handling, with a concentrated forward weight bias and narrow track, was a little more uncertain, but here was a car utterly different from the contemporary Japanese norm. It was also a machine sold in very limited numbers in Australia - a collectors' item indeed.
Other performance Skylines followed, but they made little or no export impact outside of Japan - until the R32 GT-R.
The R32 GT-R
"In a word - extraordinary. This is the world's newest benchmark... The GT-R is an awesome car, because its enormously powerful engine doesn't overpower the enormously proficient chassis." (Wheels, May 1991)
When the R32 Skyline GT-R was released in Australia in early 1991, the sales of the Prince GTB had long since been forgotten. Instead, the buzz was about the dominance of the GT-R in the Australian Touring Car Championship, where the car was walking away with win after win. Local media tests of the twin turbo, four-wheel-drive GT-R had already been carried out on grey-market imports - in fact, one company was importing the car in small numbers. But when Nissan decided to bring in one hundred of the cars, the GT-R was available for the first time as a factory-supported model. It went on sale for $110,000 in Nissan showrooms around the country - and was regarded by many as a bargain at that price.
However, it was the most expensive Nissan on sale by an enormous margin - the next most costly Nissan was the naturally aspirated 300ZX, which could be bought for 40 per cent less dollars. In fact, Nissan in Australia was a company largely selling budget vehicles like the Pulsar and Pintara - the GT-R was a bolt from the blue. In a similar way to the cultural problems that confronted Subaru dealers when they started stocking the high-performance Liberty RS, Nissan and its dealers were a little unsure of how to handle the GT-R - in the uptake of the car, and in its long-term retained value, this was one of the problems that was to dog the fast Skyline. But in early 1991, that was all in the future.
Changes for Australia included alterations to (or the additions of): side indicators, a high mount stoplight, new rear lights, child restraint anchorages, side intrusion bars, a two-position instrument light dimmer, the windscreen, side rear view mirrors, speedometer, seat belts, sunvisors, fuel filler neck, exhaust, and engine management system. Additionally, a new radio and aerial were fitted, and an under-car oil cooler was provided for the four-wheel-drive system. The cars were available in three colours - silver, black or burgundy, all with black/grey interiors.
Although the GT-R was a Skyline, Nissan distanced the car from the previous model R31 Skylines that had been built and sold in Australia. As a result, all of Nissan's advertising and internal literature said 'GT-R', never 'Skyline GT-R'. The Skyline was a simple rear-wheel-drive car that had sold in Australia for only $32,000 in its highest Ti trim level - best to call this new car just a GT-R!
There were few - if any - parts that the R32 GT-R shared with the previous R31 models that were built in Australia. This new car was muscularly curvaceous, front and rear guards bulging over 16 x 8 inch light-weight alloys - the side skirts, front spoiler and huge rear wing making the point if you didn't see the enormous, black opening beneath the number plate. Lurking behind that dark cavern was an equally enormous air/air intercooler - sized like something from a truck, when compared with the toy intercoolers usually favoured by Japanese manufacturers of the time. This was a serious car designed to win on the track and dominate on the street, a car that in its engineering made few concessions to the constraints normally posed by budgets and manufacturing considerations.
From its alloy bonnet and front guards to its made-for-racing aerodynamics, the GT-R was all big, bold and brawny.
The highlight of the car was its engine. Startlingly advanced for the time, it built upon the Japanese manufacturer's long history of selling strong, relatively small capacity in-line sixes. The RB-series bottom end was largely based on the previous L-series sixes, engines which in turn had been developed from the L-series fours. The L-series engines had shown extreme longevity and had proved themselves in world-wide rallying, however by the mid-Eighties the L-series was starting to show its 1960's heritage. The non-crossflow design, single overhead cam and poor NVH (noise, vibration, harshness) meant that a major upgrade was needed. The RB engine that was developed from it used a similarly strong cast iron block and bottom end, but had a very different upper half.
The RB-series was available in 2, 2.6 and 3 litres capacities (later also 2.5). It could be had with a single overhead cam or in DOHC forms, and with a single or twin turbos - in single turbo form both with and without intercoolers. The valve lifters could be hydraulic or solid, and the intake systems varied from engine to engine. Best of the bunch was the RB26DETT engine fitted to the GT-R.
The '26' stood for its 2.6 litre capacity (it was sized thus to take advantage of the 1.7 turbo equivalence formula used in Group A racing); the 'DE' stood for double overhead cams, which were used with solid lifters; and the 'TT' was evocative of twin turbos. (The SOHC RB30ET turbo 3-litre used in the Holden VL Commodore was a very close relation, as was the naturally aspirated RB30E used in both the VL Commodore and the R31 Skyline.)
Rated in Australia with a peak output of 205kW at 6800 rpm, the 24-valve six was actually more powerful than that figure suggested. As with all Japanese engines of the time, a manufacturers' agreement with the Japanese government prevented power outputs of greater than 280PS (207kW) being quoted; it was widely rumoured that in fact the engine developed more than 225kW. Peak torque of 355Nm occurred at a relatively high engine speed (for a twin turbo engine) of 4400 rpm.
The substantially over-square design (86mm bore and 73.7mm stroke) gave an actual capacity of 2568cc, a size totally belied by the car's performance. Pentroof combustion chambers used an 8.5:1 compression ratio, and the two exhaust valves per cylinder were equipped with sodium-filled stems. To allow for engine speeds up to the staggeringly-high 8200 rpm rev limiter, the valves were driven directly by bucket-type followers, rather than through the hydraulic lifters of the other RB-series engines.
Separate cast iron exhaust manifolds connected the engine to each of the two T28 ceramic turbos; these worked in parallel (rather than sequentially) and in turn blew through the single front-mounted intercooler. Following that, more of the engine's sophistication was on display with the large log-type plenum chamber feeding six individual throttle butterflies. The spark plugs used six direct-fire ignition coils and the turbo boost was electronically controlled by the engine management system.
While the engine was supremely competent - tractable, smooth and strong across its whole rev range - it was the rest of the driveline that demanded almost as much attention. Mounted longitudinally, the engine drove through a 5-speed gearbox to the rear wheels via a 4.111 mechanically limited slip final drive. The ratios in the 'box were quite low, giving excellent response, even when the off-boost 2.6 litre engine was trying to push along the 1530kg body mass.
However, the trick stuff was the on-demand four-wheel-drive system. Backing the gearbox was a transfer case containing a wet multi-plate clutch, operated by a separate electronic/hydraulic system. This system, called the ATESSA ET-S, was capable of transferring torque to the front wheels via a separate forward-running propeller shaft that passed through the engine's sump.
The torque-split was under the influence of a sophisticated electronic control system. Using inputs from the ABS wheel speed sensors, g-sensors that measured both longitudinal and lateral acceleration, and from the throttle position sensor, the system was calibrated to transfer torque to the front wheels only when the rear wheels lost traction. In straightline acceleration this allowed the car to be launched very hard without bogging down - the rear wheels would spin for a moment before torque was transferred forwards.
To avoid the characteristic power-on cornering understeer of constant four-wheel-drive cars, the front wheels were usually not driven while the car was cornering. In fact the electronic control system measured lateral acceleration and actually reduced the torque going to the front wheels if the car was cornering with some rear wheelspin. It was only if rear wheelspin became excessive while cornering that the front wheels came into action. The outcome of these torque movements was that the GT-R drove very much like a powerful rear-wheel-drive car, however one which behaved far better than a RWD when rear traction had been lost. (The original US patent for the torque control system is shown here.)
The suspension of the car was sophisticated but conventional. At the front, unequal upper and lower control arms were used with an additional link. Rear suspension was also multi-link, with front and rear anti-roll bars fitted. The front brakes were very large (for the time) 295mm drilled and ventilated discs gripped by four-pot calipers. At the rear, much smaller twin-pot calipers were used on 297mm discs, which again were drilled and ventilated. ABS was standard.
In addition to the four-wheel-drive system and twin turbos, the car had another technological trick up its sleeve - HICAS, which was a simple form of four-wheel steering. With this system the rear suspension subframe was moved a little on its bushes by a hydraulic ram, allowing small (1 degree) alterations in rear toe. The amount of rear steering was dependent on the speed and movement of the steering wheel, with the rears steered out of phase for a moment during turn-in before then following the direction of the front wheels.
The measured performance of the car varied enormously, with the standing start times depending very much on how hard the car was launched. This helps explain the variation in 0-100 km/h figures - standard cars in some tests are as fast as 4.8 seconds while others are as slow as 6.2! Using a moderate launch (3000-4000 rpm clutch dump) would yield times in the high fives. Nissan Australia claimed a 0-100 time of 6.2 seconds and a standing 400 metres of 14.3 seconds.
The large and heavy GT-R was an awesome car. In direct comparisons it triumphed over cars like the Mitsubishi 3000GT, Mazda RX7 twin turbo, Honda NSX and Porsche Carrera 4. On the track its wins were legendary. However, those people in the market for a $110,000 Nissan were not numerous - no matter how glowing the media reports on the car were. It took some time to sell all of the cars, and then many of them travelled only few kilometres.
Once Nissan had sold the GT-Rs that they had imported, the door to direct (grey market) imports of used cars from Japan again opened. And when these cars became available at a price nearly half that of the locally delivered cars, the value of the locals dropped dramatically. That was bad news for those original owners, but it allowed a far wider variety of people to afford a car that did more than any other to define Japanese high-tech in the Nineties - a magnificent machine with an engine second-to-none and with strong, traditional sporting car handling.
Problems
In service the GT-R proved very reliable, although - as with any car - it did have its problems. As with most high-performance four-wheel-drive turbo cars, the clutch was a weak link in the driveline - although in the regard it was much better than the constant four-wheel-drives. The bushes in the front suspension's upper A-arms wore quickly, and the engine management ECU could give trouble, sometimes evidenced by a miss that then disappeared as the car warmed up.
The aluminium front guards and bonnet dented easily (a stone was likely to leave a ding rather than just a chip), and - more seriously - the ceramic turbos could shatter if over-speeded as a result of too great an aftermarket boost increase. The steering was very much affected by the tyres being worn - with the wrong tyres it suffered from severe tramlining and kickback. Finally, the synchros on the upper gears were a little weak - high rpm, quick changes could result in some crunching.
Modifications
One of the strongest engines ever made, the RB26DETT was designed from the outset for racing use and so responded very well to modification. The Group A race teams were gaining power outputs of around 450kW from the engine, although parts like the exhaust manifolds were being replaced after almost every race (they drooped from the heat).
Replacing the ceramic turbos with conventional steel units, increasing the boost, and fitting a large exhaust can result in an easy 370kW. In terms of parts, everything from plug-in replacement engine management ECUs to complete replacement crankshafts are available for this engine. In Japan, reliable power outputs of over 750kW have been recorded. The brakes fitted to the factory-upgrade V-Spec model (which used larger Brembo front calipers) are easily swapped, while aftermarket brakes, suspension and other performance parts are numerous. However, modifying this car with good parts is not a cheap process!
If handling with less power oversteer is desired, the four-wheel drive system can be modified to allow a driver-adjustable torque split. We have covered in AutoSpeed this modification in some detail - "Godzilla Tamed".
Conclusion
The R32 GT-R is a true modern classic. It was sold with technology once only available in prestige European marques, and with performance and traditional handling to put a smile on the faces of those who had previously only been able to dream of those abilities for the price.
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