"It is necessary to drive the car to believe that such a seemingly endless surge of strong acceleration is possible from a 2.0 litre engine in a far from lightweight car." (Modern Motor, August 1978)
While the Saab Turbo wasn't the first turbo car sold in Australia, it was the first family car available on our market with forced aspiration. As such, it was the precursor not only to a breed of turbo Saabs, but also to small capacity cars that had as their aims practicality as well as turbo performance.
The 99 was first released in Australia in early 1972. A replacement for the rather odd V4-powered 96 model that had been sold here in small numbers, the Saab 99 was a far more conventional car with its British Leyland-based SOHC 1854cc in-line four cylinder. The engine was actually one-half of the 3-litre V8 used in the Triumph Stag, and was equipped with a single Stromberg CD carburettor. It was mounted longitudinally and drove the front wheels through a gearbox located under the engine. Never a car with speedy acceleration (the standing 400 metre run was despatched in 19.5 seconds) the strengths of the Saab were in its ability to cruise long distances in comfort - irrespective of road conditions - and in the quality of its construction. With 62 per cent of the mass on the front wheels, understeer was the dominant handling characteristic, but it was never deemed to be excessive.
Six years later, the Turbo 99 was introduced. It was based on the Saab 99 Combi Coupe (a three-door hatchback), and at $18,250, it was expensive - but not crazily so. The turbo 99 was about the price of a Volvo 265 wagon, putting the brand new technology within the reach of many. Back then no one knew much about turbos, as the road tests of the 99 Turbo made quite clear...
"Open the bonnet of the Saab and all looks normal until you spot, near the radiator, a mini version of the turbine you find at the end of those long descending pipes at a hydro-electric power station. But instead of being driven by a mass of water, it's driven by the surprising power of the engine's exhaust. And instead of driving a power generator, it drives a turbine (fan) which pumps air into the intake manifold where it ultimately gets the appropriate squirt of petrol from the fuel injectors." It's now refreshing to look back on the August, 1978 Modern Motor article - the complete concept of turbocharging needed to be explained in the review of the car!
Over the injected 2-litre that was also available, the Turbo lifted power by 23 per cent and torque by a significant 41 percent, with the torque peak developed 700 rpm lower in the rev range. A Garret AirResearch T3 turbo boosted to 7.5 psi; an external wastegate was used to control boost - in those days, turbos with internal wastegates weren't even available! Internal engine changes were restricted to a reduction in compression ratio to 7.2:1, and the use of a milder camshaft and stronger valves. Additionally, an oil cooler and larger radiator were fitted, while the gearing was made a little taller. However, 'taller gearing' is a relative term - with only 33 km/h per 1000 rpm in fourth (top) gear, the car could still exceed the redline at maximum speed. (A curious coincidence - the 2000 model Subaru STi has the same gearing in top gear - but with an engine redline of much higher!)
The 99 Turbo was identifiable by its badges, front and rear spoilers, and ugly 15 x 5.5 alloy wheels. Inside, there was with a tacho, a boost gauge mounted in a pod on top of the dash, and a thick-rimmed steering wheel. Nought to 100 km/h came up in 11.1 seconds, with the standing quarter completed in the mid seventeens. Top speed stretched to 195 km/h.
Today it is obvious that the combination of a T3 turbo, a compression ratio of 7.2:1 and an 8-valve 2-litre is going to give quite major turbo lag - and so it then proved. However, in Saab's defence, there were simply no smaller turbos available. Even the use of a wastegate to allow lower-rpm boost was at the time regarded as a novel idea - many turbo installations on racecars didn't use any wastegate at all. Add to that the fact that the mechanical injection and unmapped Bosch electronic ignition gave very little latitude for the type of tuning needed to give sharp off-boost response, and the 99's miserable standing-start performance times are not really surprising. But the on-boost times? They were blistering!
In fact, as Wheels magazine said in a July, 1978 test, "Compare the top gear times and you'll see that the Turbo is almost as fast between 60 km/h and 160 km/h in fourth gear as any five-seater in the world."
Not bad for a little, oddly-shaped sedan from an obscure Swedish car maker!
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