Audi's refines their S2 - Audi S2 1992 [Driven]

It was Audi which made four-wheel drive a household word back in the early 80s with its legendary Audi Quattro that certainly was a machine with a purpose. A rally machine with a turbocharged five-cylinder engine developing 200 bhp to drive all four wheels, it literally left the others standing. And by others, we don't mean ordinary everyday cars but full-fledged rally icons like the Fiat Abarth 131, Lancia Stratos and Ford Escort RS. The purpose of the Quattro was very clearly defined— defeat the opposition. This display of technological prowess was perhaps the most effective marketing tool employed by Audi. There was little doubt Audi was on Cloud Nine. With each passing rally season, the speeds of the competitors were raised to alarming levels. To keep ahead, Audi had to introduce the Audi Sport Quattro S1. It had an awkwardly short wheelbase to confer more agility and had the 20-valve head to push out some 400-plus Bhp in rally trim. By then the world motor sports authorities had about enough of the special Group B cars because the speeds were becoming very dangerous as the battle of factory teams, namely Peugeot, Lancia, Ford and Audi ensued. Promptly, Group B cars were banned and Group A cars were introduced into the regulations.

It has been 10 years since and memory of the original Audi Quattro have faded. In those 10 years, Audi introduced its all wheel-drive technology to its passenger range of cars with some success. For a brief season, it even tried its hand at the World Rally Championship with a competition version of its Audi 200 quattro. Needless to say, it was just a little too big to make any impact on the rally like the Lancia Delta HF 4WD, though it did bring home some limited measure of success. However, Audi realized the advantage of an all-wheel drive not to mention its prestige value.

But why introduce the Audi S2 only now? Actually, it was more in the Spring 1991 but it has only this year been introduced locally. Audi would very much like to be able to capture sufficient local market share to put it alongside BMW and to this end, it has deployed all the marketing strategy it could muster for the task. The S2, as you may have guessed, is the technological spearhead that it needs. It is the way of displaying the "Vorsprung durch Technik" of Audi. It is however no rally-going machine like its ethereal predecessor, the Audi S1 Quattro. No, this is a very civilized super sports coupe, meant for those who lust for a German techno-missile of the Quattro kind.

Packing the same rally winning 20- valve, turbocharged, 2.2-litre, five-cylinder engine, the engineers have settled for an output of just 220 bhp, a far cry from the 400 bhp in the original S1. What Audi has done, and sensibly too, was to tune the engine for low RPM peak torque. A massive 309 Nm is available at just 1950RPM. Now, that is what we call low end torque although in actual use, you'd be hard pressed to find it there. Remember this figure is when the engine is on full boost. In practice, by the time the turbocharger gets up to speed in 1st gear it is already 2,800RPM. Just from looking at how the engine barely manages to fit within the confines of the 80 Coupe's engine bay, we can only conclude that it must have been one great "shoe-horn" exercise for the engineers. For some reason only known to Audi, there are two radiators. We thought that it may be the water to air intercooler but we soon discovered that the S2 has an air-to-air intercooler. And on top of that, Audi has fitted two catalytic convertors to be doubly sure that emission standards are complied with. Another surprise is the 9.3:1 compression ratio, a figure considered pretty good for a normal aspirated engine but is definitely on the high side for one that is force-fed to the tune of 100 bhp per litre. In most engines with this state of tune and that much boost pressure, just about the only noise one will hear from the engine when the turbo spools up to speed would be not unlike a bunch of marbles rattling, a classic case of uncontrolled detonation or "knock". With careful design of the pentroof combustion chamber and the use of
knock sensors, it would be difficult to see compression ratios any higher than the excellent 9.3:1 (on 95 RON petrol!) in the S2.

On the road, the engine delivers avery refined performance. It is smoother than the previous 5-cylinder 90 and does not display the typical "on-off" temperament of a typical turbo installation. Power is delivered in seamless fashion, but there is no mistaking the hurried exponential way which acceleration builds up as the turbo comes on. It is not at idle which best reflects the engine's newfound refinement but rather when the engine is brought up to speed where it remains relatively quiet and composed. Both induction roar and exhaust noise have been banished from the S2's repertoire. Despite the implied lineage via the S2/S1 name, the S2 is a very civilized in comparison. That may irk sonie purists but don't forget that Audi has retired from the scrummage of its adolecent past and has now has donned an Armani suit.

Multiplying the engines useful torque is a slick and accurate gearbox. At first, it is not obvious that it his been specially fitted out with ratios that help fill out that turbo lag. With repeated use, one will notice that shifting to 2nd after1st gear reaches the redline at 7100 rpm, the engine starts up again at about 3,500RPM, about half the available revs. Audi has provided the S2 with a low 1st gear and a tall 2nd. By shifting at the red line, one is actually producing the characteristics of the short shift, but with on difference. Since the 1st gear ratio is so low, the car can really get a move on fron standstill, side-stepping the turbo lag probleem and at the same time kicking the turbo charger up to speed. So not surprisingly, the action starts getting pretty dramatic in 2nd and 3rd gears. If this car had but one pair of driven wheels, the wheelspin produced by the 309Nm of torque would be largely uncontrollable. Channeled through all of them, the tyres produce barely a chirp even during the most violent take-offs. Traction off the line was incredible and this certainly helps its 0-100 km/h times.

However as we found out, with 4WD cars it is not matter of dumping the clutch and let the tyres sort out the acceleration. With such a surfeit of grip, the engine's kinetic energy will be absorbed in one big lurch landing the revs some way below the point where the turbocharger actuall gets going. What one has to do is to feed the revs through the clutch, not just merely letting it go. This allows the turbo to build pressure sufficiently as the car's speed catches up with the transmitted power. Using this technique, the Audi S2 zips to the century mark in a scant 6.1 seconds. At first, it doesn't feel all that fast but that is because of the refinement of this car. The aural sensation of speed is hidden away and what's left is this seat of the pants experience. The engine barely works up a bark and the well honed aerodynamics (0.32 Cd) parts the air without much disturbance. But perhaps the biggest factor is the car's excellent sound insulation. Extraneous noise are completely shut out just by closing the heavy door.

After a while, one comes to appreciate the Audi S2 as it gets moving. It is effortless, there is no strain displayed by the engine as full power is applied. Turbocharged motors always manage to produce an effortless swath of power that escapes the ability of a normally aspirated engine. Even with high lift cams, the normally aspirated engines scream with a hunger for more air at ever increasing RPMs while the turboed engines are literally stuffed full even at low revs. Indeed, the way the turboed engines shape their torque curve, could not be better suited for normal driving as there are but a few crazed enthusiasts who would rather spend all day with their engines screaming at 6,000RPM. It is too bad that there is the phenomenon called turbo lag. Good though the S2's installation is, there is some waiting to be done if full propulsion is called for after slowing down. Enough to be an irritation.

Even as all the horses are called to the fore, the engine remains smooth, much smoother than we remember it. Audi has obviously been hard at work. There is a small but detectable 5-cylinder beat but it is well-muted to make this engine superbly suited for cruising as well as "cannonballing". Another revelation is that this car's ride is rather good. Sure it is firm but there is a yielding suppleness to it over the rough bits. The tyres of course have their part to play, their soft compound contributing to the apparent comfort as well as the enormous grip. The 205/ 55 ZR 16 Klebers don't pound their 55 series character into the car's interior although they do display some pattern noise which is smothered by the superb insulation.

Pressed to the limit, the car understeers initially. As power is applied the car moves into an unusual neutrality. For most cars, neutrality is a phase where the limit of the rear grip is breached and begins mitigating the understeer at the front. With the S2, the power distribution merely changes the slip angles so the car traces a neutral arc, leaving the tyres grip unaffected. The Torsen centre differential splits torque nominally at 50:50 but can split anywhere from 75:25 to 25:75. It balances all the tyres at their limits and since on tarmac, no one axle can be overwhelmed by power, the S2 can really launch itself out ofcorners at incredible speeds.

The operative word here is balance. Enter the corner without power, and the S2 goes round like the Audi 80, understeering. Power through, and the car assumes a neutral stance and this ability is no better demonstrated than in the rain or on low friction surfaces. Confidence grows with exploration of the car's limits and full throttle application is suitable almost anywhere. As we discovered, full throttle could almost be a full-time affair provided one remembered not to defy the laws of gravity though it was more the law of the land that would be holding back the right foot.

The S2 comes with an assisted-steering system at the very cutting edge of technology. Servotronic is a system using linear motors to drive the rack instead of hydraulics. On a quiet road, the strain gauge can be heard as one cranks the wheel over. It is a great idea, but too bad it is too efficient. The feel is a little too light and feedback is masked. Good thing that the S2 comes with an unflappable chassis which despite the Servotronic, manages to shine through. Full lock is easily achieved but this only results in a turning circle of 11 .4m, somewhat larger than average but a necessary design consideration in order to have robust and long lasting CV joints up front. The attractive sports steering wheel is connected to an unmovable column as the Proconten (Programmed Contraction and Tension) system does not allow an adjustable steering, but then again which Audi does?

So we come back to the first question. Why the S2? Afterall it has the same interior as the Audi Coupe and the Audi 80/90 but it does have an interesting new dial face that is white in daylight and pastel grey when the lights are on. There are even additional gauges but these are stashed below the aircon controls where the ash-tray used to be. But where's the boost gauge? There is none, instead you'll have to call it up on the computer readout. Audi seems to have bent over backwards trying to stuff as much technology into this S2. Witness the solar sunroof that powers the air vents and blower when the car is parked in the sun. It works! How about the name, "Quattro" formed by the heating element at the rear window? Details such as these will delight the enthusiasts. There are many more gadgets, too many to mention here, but they all seem to work. They certainly must be trying to justify the S2's price tag. At $258,000, it hardly looks that expensive mainly because it resembles the Audi 80, but there was a profound sense of loss when the time came to return the keys. The Audi S2 has won our hearts. Fast, comfortable, carries four and handles well, the Audi S2 is the consummate performance car. It is our choice for an inconspicuous sports car with near supercar performance.

Fast Facts

ENGINE
CAPACITY : 2226cc, Turbocharged
CYLINDER LAYOUT : In-line 5
VALVES : 20-valves
COMPRESSION RATIO : 9.3 : 1
MAXIMUM POWER : 220 bhp at 5900 rpm
MAXIMUM TORQUE : 309 Nm at 1950 rpm

TRANSMISSION
TYPE : 5-Speed Manual
DRIVEN WHEELS : All, Torsen center diff, locking rear

PERFORMANCE
TOP SPEED :
0-100KM/H : 6.1seconds

SUSPENSION
FRONT : MacPherson struts
REAR : MacPherson struts

BRAKES
FRONT : Ventilated Discs
REAR : Discs

TYRES
TYPE : Kleber
SIZE : 205/55 ZR 16

SAFETY
ABS : Yes
AIRBAGS : Nil
TRACTION CONTROL : Nil

KERB WEIGHT : 1420 kg
TURNING CIRCLE :11.4m

Price in 1991: $258,000 SGD

 

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