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This article was first published in 2001.
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When the naturally aspirated N12 Nissan Pulsar was first released - back in November 1982 -- small cars were slow. Very slow. The Pulsar was available with either a 1.3 or 1.5 litre carby engine, and even when the 'big' 51kW engine was fitted, the manual five-speed ran the standing 400 metres in a snail-like 19.2 seconds. Nought to 100 km/h came up in a touch over 14 seconds - but in those days, this type of performance was regarded as acceptable in a small car. At least the Pulsar boasted modern body design touches like steeply-raked front and rear screens, wrap-over doors without external rain gutters, and, in the five-door version, a large hatchback. (A coupe was rumoured to be in the pipeline - but no one knew anything about it.) The chassis of the Pulsar was also up to the mark with independent trailing rear arms, struts at the front, and rack and pinion steering.
By May of '83 the Pulsar was being assembled locally in Australia. Nissan took advantage of the 70 per cent local content to fit improved seats, a new dashboard, and a bigger ventilation fan. More importantly, progressive rate springs and a rear anti-roll bar were fitted, along with new dampers and wider tyres. Nissan knew the exact demographic buying the car - their research indicated a typical buyer to be a cinema-going woman, interested in gardening and who wanted a car easy to drive in the city. And that's the way that the car might have remained - a competent, slow, small family car, by now available as a booted sedan as well as a hatch.
But Nissan had something startling waiting in the wings...
The Pulsar EXA
"Extraordinary EXA - high performance with low price. It leaves the small car class gasping for breath..." (Wheels, November 1983)
Just six months after the release of the locally-built Pulsar, Nissan introduced the stunning Pulsar EXA. Fully imported, the car featured a turbocharged and electronically-managed version of the 1.5 litre engine. And the engine was the really big news - a turbo car in totally foreign pricing territory. Sure, there were already turbo machines available in Australia - the $24,000 Mitsubishi Starion, the $27,000+ Saab, the $63,000 Lotus Espirit and the even-more-expensive Porsche 911. But the EXA was just $11,950 - it may have cost 37 per cent more than a normal Pulsar, but then again, this was a bird of a totally different feather to the car on which it was based.... The EXA bought affordable turbo hi-tech to the market for the first time.
Heart of the new car was the transversely-mounted, four cylinder, turbocharged E15ET engine. The re-engineering of the engine for its forced aspiration role was quite extensive. While it shared its long-stroke (76mm bore and 82mm stroke) swept dimensions with the naturally aspirated 1.5, there were many other differences. The strengthened con-rods were shortened by 3mm to reduce compression from 9.0:1 to a more turbo-friendly 7.4:1, piston rigidity was increased, the top piston rings were chromium plated (for improved wear resistance), and the gudgeon pins were strengthened.
A heat exchanger (through which coolant was circulated) was fitted to reduce oil temperatures, and an auxiliary electric radiator fan was used to blow cooling air over the turbo and exhaust manifold. The crankshaft had rolled fillets and the valve seats were stellited. The Nissan/Garret T02 turbo featured an internal wastegate and was one of the first of a new breed of tiny turbos designed for low-lag application on small four cylinder engines. It used a peak boost pressure of 7 psi, and as with other Nissan turbo engines of the time, no intercooler was fitted.
While the standard Pulsar was fitted with a conventional carburettor, the EXA used full engine management, with an Electronic Control Unit handling both fuel injection and ignition demands. The system - dubbed by Nissan ECCS - was based largely around Bosch components. Highly advanced for the time, it used a vane-type airflow meter, knock sensor and other inputs such as crankshaft position, coolant and intake air temperature. Depending on the fuel demand, the injectors could be fired in two modes and the ignition timing could be retarded if detonation was detected. The turbo boost pressure was not controlled by the management system, but instead by a conventional wastegate system.
The result of this massive engine upgrade was an improvement in power of 51 per cent to 77kW at 5600 rpm, with a torque increase of 36 per cent. Indicative of the small, well-matched turbo was the fact that peak torque occurred at the same revs in both the naturally aspirated and turbo engines. Actual gearing was not altered over the normal Pulsar - although the final drive was changed from 3.789 to 3.550, the km/h per 1000 rpm figures remained much the same because of revised tyres. While the EXA was 80kg heavier than the Pulsar sedan, it was still about 1.5 seconds quicker over the standing 400 metres and a major 4.4 seconds quicker to 100 km/h - the EXA did this standing start run in a neat 10 seconds flat.
The underpinnings of the EXA were effectively identical to the sedan. Rear drum brakes were used together with the front discs, while in the late 1984 update model, ventilated front discs were fitted along with progressive rate rear springs. Other alterations for the update were interior changes (although many of the earlier model were sold with optioned-up interiors anyway) including carpet-trimmed lower doors, a digital clock, new steering wheel and a driver's footrest.
Styling of the coupe was probably its most contentious point. A sharp-edged car with a very upright rear window and wedge-shaped nose complete with pop-up headlights, the two-door didn't have the neatness and visual cohesion of the Pulsar Hatch - but then again, it had some extreme performance advantages, too!
What was really needed was a combination of that engine with five doors. Nissan thought so as well....
The Pulsar ET
"Extra Terrific - one of the most significant progressions in the Australian turbo industry." (Turbo Australia #5)
It was June 1984, and the Australian motoring media were greeting the arrival of the Pulsar ET with much acclaim. Here was the car that people had been waiting for - the sophisticated and powerful 1.5 litre four from the EXA, with the practicality and inoffensive good looks of the five-door Pulsar hatch. And the reason that 'Australia' was so frequently mentioned in the media coverage is that the car's combination of features was largely Australian-developed. Unlike the EXA, the ET car was built in Australia and it featured Australian suspension settings and an Australian-developed interior. Of course, the fundamental design of the body, engine, turbocharging system and electronics were all the product of Japan - but the car itself was unique to Australian shores.
Over the Pulsar hatch, the ET gained large front and rear spoilers, 14-inch alloy wheels wearing 175/65 tyres, and four wheel disc brakes. The new rear discs were developed by Repco-PBR for the ET and were part of a heavily-tweaked chassis - the front springs were changed from progressive to linear rate design, the front and rear anti-roll bars were altered in thicknesses, and spring and damper rates were upgraded, with the rear dampers altered to a twin-tube design. Making a great improvement in ride comfort was the fitting of Bluebird TRX seats, which were clad in wool-blend upholstery. As with the EXA, all ET Pulsars were fitted with five-speed gearboxes.
Performance of the ET was virtually identical to the EXA, with variations in performance times due more to normal manufacturing and run-in tolerances than anything else. Although the ET was a little heavier than the EXA, the change in mass didn't cause much difference in acceleration. Top speed was also unchanged, despite the ET having better aerodynamics. The real gains of the newer car were in handling and five-door practicality.
A well-integrated package that combined good handling with excellent throttle control, the ET was at its best on flowing roads where the strong mid-range torque, tall gearing and fluid chassis came together beautifully. However, these days the lack of power steering and the wind noise (noticeable from as low as 90 km/h) are downers. The engine management also causes a surge after lifting off for each gear change - part of an emissions-reduction strategy.
The Unleaded Cars
From January 1, 1986, all cars sold in Australia had to run on unleaded fuel, with both the EXA and ET modified by the manufacturer to run on the lower octane brew. Although the compression ratio was raised from 7.4 to 8.0:1, peak power on the lower octane fuel dropped from 77kW to 75kW, with torque down marginally from 157 to 152Nm. (Both maxima were still developed at the same rpm.) For unleaded fuel, a catalytic converter was added to the exhaust and the engine management system gained an exhaust gas oxygen sensor. The turbo was significantly upgraded, with the previous air-cooled design being replaced by a water-cooled version.
Conclusion
With many turbo Pulsars now rough around the edges, it's easy to forget that the EXA - and to a greater extent, the ET - were in their day regarded as very sophisticated, high performance fours. It would be an overstatement to suggest that they were to the mid-Eighties what the Impreza WRX is today, but comparisons with cars like the contemporary Peugeot 206Gti are much more valid.
I wonder how long it will be before people start to restore them to pristine, original condition?
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