While there are some cars that are on everyone's list for modification, there's also a whole swag of four cylinder turbo cars remaining largely untouched. So if you're after a four with more - and don't want to be seen in just another Pulsar ET, Cordia Turbo or Swift GTi - what else is there available which will give cost-effective but sophisticated grunt?
Saab 900 Turbo
Saab were the pioneers of the whole turbo revolution in mass-produced passenger cars. Way back in '72 they introduced the naturally aspirated 99 range, followed soon after by the 99 turbo, which pumped out 108kW on 10 psi boost. When the Saab was tested in Australia, one magazine compared it with the 5 litre Holden Torana A9X - against which it was faster in all acceleration increments over 100km/h. Getting to 160 km/h took only 24.6 seconds - not hanging around, and back then bloody sensational from only 2 litres.
But the 99 is now very long in the tooth. Replacing it was the 900 series, with the first 900 turbos coming to Australia in late 1979. Running a non-intercooled two litre SOHC 8-valve engine, they used mechanical K-Jetronic injection and a five-speed box. By '83 the car had metamorphosed into the intercooled twin-cam 16 valve version, with up to 131kW available. The 1985 Turbo Aero could sprint to 100 in 8.6 seconds, and go on to a top speed of 220 km/h. The standing quarter was done in the high fifteens.
The first 900 Turbos are now dirt-cheap - A$4500-A$7500 should buy you a good one. The engines can run a long, long time, with one owner having racked-up a staggering 300,000 km with only routine maintenance. Parts prices aren't as high as you might think, either, with a complete used turbo engine worth about A$1500.
Performance upgrades are there for the taking. The standard air-cooled turbo can be swapped for a high-flow water-cooled T03 to improve top-end performance, which in the standard car starts to die over 4500 rpm. To really exploit the top-end the rev-cut needs to be disabled, and this is easily achieved by swapping the dizzy rotor for a Volvo unit. Boost of up to 17 psi can be run. Normal exhaust upgrades can be made, with a 3-inch pipe giving a noticeable increase in performance over a 2.5-inch design. An air/air intercooler core can be fitted behind the front left headlight, while the K-Jetronic mechanical injection system is easily modified to provide more fuel via the boost enrichment circuit.
The only major weakness in the drivetrain is the gearbox, which tends to destroy the needle roller bearing on the cluster shaft. The best fix is to use the later gearbox from the later model 16 valve intercooled cars.
Holden Piazza Turbo/Isuzu Impulse Turbo
Mixed-in with the conventional mid-eighties offerings from GM was the Isuzu-built Piazza. Released in Australia in 1986, the car retailed for A$35,000 - when a Cordia Turbo was A$21,000! With a 0-100 time of 9.3 seconds and a standing quarter of 16.8, the car had some get-up-and-go, but unfortunately the performance level dropped pretty severely when any corners arrived. The widespread reaction to the car's handling was so critical that the price was soon reduced to A$29,000.
But, given the way the used car price of the Piazza has crashed (it's about A$8000 now) is it perhaps worth another look? The answer's 'yes' for two reasons. First, the suspension is largely based on the RWD Gemini - and Geminis can be made to handle very well. And, secondly, those eight Gs buy you a package that includes a helluva lot of good stuff.
Under the skin is an IHI turbo blowing into a 2-litre SOHC engine (a close relative of the Gemini mill), producing 110kW at 5400 rpm and a hefty 225Nm at 3000 rpm. There's also a long standard equipment list which includes four wheel discs, power steering, power windows, digital dash, central locking, and so on. The auto is a four speed with a tall 0.689 overdrive, and an LSD is standard. The Giugario-designed body is both pretty and aerodynamic, and helps give the car a near-200 km/h top end.
The engine runs L-Jetronic injection together with a separate ignition system. This means that a chip-swap isn't available, because the EFI doesn't hold any maps within a chip. However, hard-wiring changes and airflow meter recalibration should be able to be made to cope with major fuelling upgrades.
Performance mods could start with the suspension, and then move onto the standard exhaust-EFI-boost route. A 25 per cent increase in power - which should be pretty easy to achieve - would give the car a power/weight ratio which should give 0-100's in the low sevens. Another advantage in these days of almost universal front-wheel drive is that it's a RWD car!
Charade G11 Turbo
Here's one for tight budgets - A$3000 will get you into a good boosted Charade. Released in June 1984, the little car ran a one-litre three-cylinder engine producing 50kW at 5500 rpm and a torque peak of 106Nm at 3200 revs. With a top speed of around 160 km/h and a standing quarter of 17.1, obviously the Charade isn't a ball-tearer - but it's willing and the fuel economy (5.3 litres/100 km) is better than almost any other car on the road.
Although the car was criticised for limited suspension travel when it was first released, the tiny factory alloys clad with 165 tyres still gave good handling for the time. Optioned-up versions saw relatively large 185/65 series rubbers all round, which made it stick to the tarmac tonnes better. Upgrades over the atmo suspension included stiffer front and rear springs, a hollow 21mm rear sway and a solid 24mm front bar. The rear (hollow) axle uses four links and a Panhard rod to locate it. The turbo model also ran a higher steering ratio than the atmo car.
There were two versions of the G11 turbo. The later 'G11 update' model received a different nose and tail lights, improved interior and some minor under-skin alterations.
A blow-through carby system is used in both cars, with the IHI RHB32 turbo pumping at about 7 psi. The 3-cylinder SOHC engine uses a cast iron block and an aluminium cylinder head, and the turbo model has significant 40 per cent more power than standard. Both fourth and fifth gears are overdrives (0.864 and 0.707 respectively), and no LSD is fitted.
Because it's a blow-through system the engine can be intercooled, and there's plenty of room behind the grille for a mid-sized 'cooler. With an exhaust, intercooler, intake mods and around 16 psi boost, they are capable of a character building 15.6 second quarter! Or, if you're on a higher budget, the later-model injected DOHC GTti engine (with 75kW) can be slotted under the bonnet without any major mechanical mods.
When new, the car was billed as the cheapest and most economical turbo car in the world - and not much has changed since.
Subaru Vortex and RX Turbo 4WD
Lost in the blaze of glory of the Impreza WRX is the humble Subaru RX and Vortex 4WD, which were both released with a turbo and 4WD over 15 years ago. While they're not nearly in the same league as the WRX in sophistication or performance, they are still worth a look because they're probably the cheapest way to get into a factory 4WD turbo car.
Both cars were first released to rally teams in 1984, with the cars sold from 1986 to the general public. The RX featured an on-demand 4WD system which owed more in its design to off-roaders than the Audi Quattro - Subaru recommended that 4WD be selected only when on dirt or slippery surfaces. The car was also available as a 3-speed auto, with the 4WD automatically selected whenever the car was accelerated or braked hard, and whenever the windscreen wipers were switched on! However, contemporary tests indicated that it was only when doing tight turns on firm surfaces that the 4WD system (which doesn't have a centre diff) got unhappy. The Vortex 2 door came with the choice of either an on-demand or constant 4WD system, depending on the transmission selected. The auto versions all scored the permanent all-paw surefootedness, which helped them exit corners efficiently no matter what the road surface.
Their four-wheel-drive chassis certainly gave these cars a huge straight-line traction advantage. With only 83 kW available in standard form, the car's performance times were never going to be outstanding - but four-wheel drive traction sure quickened them off the line. Testing of the RX indicated that with front wheel drive selected the standing quarter took 17.8 seconds, in Low 4WD 17.7 secs, and in High 4WD 17.5 secs. The Vortex has very similar performance, but its best recorded quarter mile time is 17.3 seconds.
The all-alloy SOHC-per-bank EA82 turbo engine produced 181Nm at just 2800 rpm to go with the peak 83kW, and the non-intercooled intake system used 8 psi from its small IHI RHB5 turbo, with L-Jetronic injection providing the fuel.
Four wheel discs combined with front struts (or air suspension depending on trans selection) and rear trailing arms with sway bars at both ends gave the cars competent handling - especially with 4WD. However, understeer was the main handling trait. Standard equipment included niceties such as alloys, power mirrors and central locking.
The rally guys kept their cars largely standard, just lifting boost to 15 psi and using a big exhaust. Other than mandatory safety equipment, the rest of the cars were bog-stock, although an extra two litres of oil were often used to over-fill the gearbox to better lubricate the gears when constantly using 4WD. The rally cars were getting about 30 per cent more grunt than standard via the simple mods. One bloke I know who played with his RX sedan claimed that it was even possible to get all four tyres smoking!
Mitsubishi Starion (Conquest) Turbo
In the early '80s, Mitsubishi's performance pride-and-joy was the RWD Starion. With its angular 'high-tech' body design and fuel injected turbo engine, it was instantly recognised as the beginning of a new wave of Japanese sports cars. Today the mighty Starions are getting a bit thin on the ground, but it's because of this (and the fact that some people find their styling questionable) you can pick them up bulk-cheap. Expect to pay around A$3-9000 depending on the model and condition.
The first model (the JA) came out in Australia in 1982, which was then bettered by the JB model with its improved intake system. The very last of the Starions that were delivered to Oz were the JD unleaded-fuel cars that also came equipped with an air-to-air intercooler among some other changes. But despite this, the low-octane fuel burner was still much slower than the dirtier engined cars.
The engine was modelled on the Sigma block and got its extra power through a Garrett-based turbocharger and a throttle-body EFI system. Earlier leaded engines produced 125kW at 5500 rpm, with the unleaded versions falling to 110kW. This had a definite effect on straight-line performance; 16.2-second quarter mile versus 16.5. Certainly a car designed with racing in mind, the large-ish 2-door handled commendably well for an example from that era. Braking was perfectly up to the job with well-sized discs at each corner. Of course, with up to 125kW, power oversteer was just a right foot prod away.
Potential is one of this car's strong points. With the usual exhaust, intake, intercooler and boost upgrades, leaded engines can spit out around 160 usable k-watts. And there's plenty more left in reserve - the contemporary Starion racecars used to thrash out 350kW while running on high-octane jungle juice!
Just how fast do you want to go?!
