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This article was first published in 1998.
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Most sports car enthusiasts have heard of the Lotus Elise. Some may even know of its startling performance. Others may just recognise it as one of the sexiest looking sports cars on the road today. But how many people really know what makes the Elise tick?
As the Australian Lotus factory driver I'm in a unique position to reveal some of Elise's little secrets and show you over an undressed Elise chassis.
The car shown here is not a standard road-going Elise, but a factory-prepared race car - the Lotus Elise Sport 190 which I have campaigned in the Australian 1998 GT Production Car Championship. The car is from the stable of Lotus dealer Monarch Motor Imports. Throughout the season we pitted our car against the might of the Porsche 911 RSCS, Ferrari 355 Challenge, V10 Dodge Viper and Maserati Ghibli Cup - and quite frequently we were able to finish in front of these cars!
This led to many an impressed spectator straining their necks in an effort to look for the high tech powerplant hidden in the back of the Elise. More often than not, they asked the question - where on earth has Lotus hidden the turbocharger? On paper the engine figures don't tell the full story. Four cylinder, EFI, 1800cc, twin overhead camshafts, four valves per cylinder and naturally aspirated! In standard trim it's good for 88kW (118hp) or in our case 142kW (190hp) for the Sport 190.
Impressive figures but hardly a match for the super cars mentioned above. So how can this possibly be, I hear you ask. Superstar driver, perhaps? I'd like to think so, but more realistically it comes down to one thing - weight. Or, more to the point, a lack of weight!
The true secret to the Elise's startling performance is a full aluminium chassis weighing just 70kg. That's about the same as its driver! Added to this is its (unique to the car industry) method of construction - hollow extruded aluminium box sections bonded together with a special heat-cured resin. This forms a semi-monocoque construction similar to that pioneered by Lotus in early Eighties Formula One race car design. The upshot is a particularly torsionally rigid and strong base on which to build.
Lotus fans will be familiar with Lotus Cars founder Colin Chapman's philosophy of "less is more". In the Elise this is true in every respect. The cockpit area is bare aluminium, equipped only with a heater (essential for demisting), Stack instrument panel, small Momo wheel - and that's about it! In the road version you'll also find a CD stereo tuner but as for air conditioning, forget it! Two sports seats are fitted but only the driver's side is adjustable. By eliminating the passenger side adjustment mechanism, more unnecessary weight can be saved. The pedals are also constructed of aluminium extrusions and are fitted close together in such a manner to allow "heel and toe" techniques to be easily applied.
Back to the engine and drivetrain. These components are in fact not Lotus-designed at all, but are supplied by Rover. The components are externally modified by Lotus to allow the fitment of competition inlet trumpets and a huge carbon fibre airbox. The airbox sources its supply from a duct provided just behind the passenger side door.
Standard extractors vent the waste gases through a sports muffler system that we developed in Melbourne. Dyno testing indicated an increase of around 5hp over the standard sports system. The gearbox and selector mechanism are essentially standard except for the fitting of closer ratios than that provided in the road-going Elise. An open differential is common to both the Sport 190 and standard Elise, however we fitted a Torsen-type limited slip diff to overcome wheelspin.
Again following the purebred race car theme, the suspension is classically simple but very effective. Double wishbone front and rear, adjustable front anti-roll bar, and Koni 2812 adjustable dampers sprung and valved to provide a stiff but compliant combination. The results? - exceptional front grip with just a hint of oversteer - just the feel that any good sports car should have. The suspension layout is essentially the same as its road-going counterpart; only the dampers and the springs have been replaced. The standard Koni and adjustable spring platforms with the Lotus uprated spring package just didn't provide the scope of adjustment to get the most out of slick racing tyres.
The wheel hub - or, more appropriately named - the upright, again follows the aluminium extrusion theme. It provides a simple to manufacture and lightweight attachment point for the wishbones. Camber adjustment can be made quickly and simply by removing or replacing shims. Rear toe and bump steer can be altered with a spherical-jointed track rod.
Also mounted from the uprights are twin spot calipers front and rear that work on drilled and ventilated cast iron discs. Again uninspiring on paper, but they provide an awesome amount of stopping power. On the standard road-going version of the Elise, the brake discs are made from a revolutionary matrix of ceramic and aluminium, providing less unsprung weight for enhanced handling characteristics. However, in the heat of competition, the chance exists that these aluminium discs may overheat hence the use of the cast iron discs on the competition version.
Everywhere that you look on the Elise, weight-saving techniques are employed. The Sport 190 boasts front and rear clamshells (bodywork) constructed from carbon fibre.
These two parts make up approximately 75 per cent of the bodywork and weigh in at a combined figure of just 20kg!
The remainder of the bodywork is constructed from fibreglass. The only exception to this is the engine cover, which is aluminium. In making a car this light you may question its structural integrity in an accident, however this too has been addressed. Frontal impact protection is by a large deformable fibreglass crash structure, once again technology derived from Formula One. All the rearward boot area is designed as a crumple zone and the immediate cockpit area is not only protected by a large diagonally braced roll bar but also by more extruded aluminium box sections hiding inside the doors. These latch directly to the main roll bar. From my experiences, this has to be one of the safest sports cars on the road.
Now you know the power and the incredibly light construction techniques - so how fast do you think the Sport 190 is? The 0-100 km/h figure is a staggering 4.4 seconds! All-up with wheels and tyres, the Lotus tips the scales at a minuscule 705kg - and that includes all of the safety equipment necessary for racing. The single heaviest part of the car when on the track is the driver - if only I had been born jockey size! Then we might have actually won some races this year....
In this, the 50th anniversary of the founding of Lotus, I am sure that in heaven somewhere the enigmatic Colin Chapman is grinning and throwing his traditional black cap in the air with joy. The Elise thoroughly deserves the name of Lotus...
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