Lotus Elise
The Elise is named after Romano Artiolli's (The head of Bugatti I believe) Grand Daughter Elise. It has an Aluminium chassis and revolutionary bonding, which is amazingly strong, yet astonishingly light, weighing only 678 Kg! It shares its 1.8 Litre Rover K Series engine with the MGF, but it is a third lighter! The aluminium alloy frame is not at all new, It is its simplicity in design and the ingenious way it exploits aluminium extrusions which is so appealing.

What is an extrusion? The word comes from the Latin words for 'out' and 'thrust'. Metal is forced through a die, engineer-speak for a slot like hole, shaped say, in an L; the metal extruded through the L comes out as an aluminium girder or beam with an L shaped cross section.

As pure aluminium is so soft it is useless structurally, Lotus produced an alloy using 1 or 2 percent of magnesium and silicon, giving it a maximum pulling strength of 16 tons per square inch.

There are different ways of joining Aluminium alloy beams to form a frame. In Audi's A8 the body frame is plugged together with special cast aluminium joints. Renault's Spyder uses welding. The Elise chassis is bonded - glued - using epoxy resin. Bonding metal chassis parts together is the engineer's dream. In a pressed sheet-steel car it is the equivalent of continuously welding every seam instead of spot welding. Try to pull a spot-welding or riveted seam apart and the stress on the seam is concentrated at each spot instead of being spread around the whole continuously welded seam; it is obvious which is stronger. Lotus could have welded the extrusions together. The disadvantage of Aluminium is that welding makes the designer use thicker-walled extrusions than the structure may need in order to be strong enough, and welding heat tends to produce a distorted chassis that has to be straightened afterwards. When large section extrusions are used, you want wall thickness to be pretty thin; in the case of the Elise, even the 2 mm minimum wall thickness allowed by extrusion was more than its designers needed in several cases. If, however, you can be sure maintain large areas of bonding - to spread loads and avoid the bonded joint peeling part under load - thin walls are no problem. Bonding allows the structure to be lighter as well as distortion free during its making. The result is the extremely stiff yet lightweight (143 lb) Elise Chassis. It is basically two long four inch wide side extrusions deepened to roughly a foot along the cockpit sides, joined by closed box - section members. From the front there is one formed by front cross-members, then another pair ahead of the pedals, a high one whose back faces doubles as the fascia and steering wheel column carrier, a shallow, wide one on the floor under the front seats, and a full depth box at the back of the cockpit over the fuel tank.

Closed boxes like these are inherently stiff. Richard Rackham, senior designer responsible for the chassis says it is as stiff as a BMW 3 Series saloon. It should mean better handling, fewer rattles and little scuttle shake.

Anyone looking at the Elise chassis will quickly spot some obvious extrusions. The pedals are slices cut from an intricately cross-braced section, but perhaps even more striking are the suspension uprights done the same way from a deliberately thick-walled heavy section.

Brake disks are aluminium metal composite racing items made from a mixture of aluminium and silicon carbide.

The body, designed by in-house stylist Julian Thompson, provides aerodynamic down-force, which can be enhanced with an optional rear diffuser. There is virtually no interior trim; the extrusions side members are styled to make acceptable cockpit features.

The MGF transverse K-series engine and Rover transmission sit on largely original mounts. As Rod Mansfield, Lotus managing director since mid-August says: 'The K-series engine is the lightest production four cylinder engine of its capacity anywhere, so it is perfect for the Elise.' There is room for bigger engines including a V6 K-series.

Elise's history is interesting. Lotus's chief engineer, vehicle design, Ken Sears, circulated a suggestion for a back-to-basics lightweight sports car in mid 1993. Executive engineer Tony Shute says: 'From Elan experience we knew there was still a market; in addition, as I'd nicked all the engineering research budget to finance the project, Lotus Engineering wanted something on return - to demonstrate Lotus technology to client world-wide.'

In September 1993, Rover expressed interest in the project, even to the point of possibility co-operating in the manufacture, but that was before the January 1994 take-over. Sensing delay, Rover wisely told Lotus to go ahead on its own. The Norfolk company's decision to give the M1/11 (as it was originally known) the green light was made in April 1994

In the light of Bugatti's (Lotus's owners) financial problems, the Elise may be a useful advertisement to potential buyers of this company and its engineers. Lotus plans to make a break-even minimum of 700 a year of this delectable £20,000 baby.

Lotus Esprite V8
.The Esprit series started in 1976. During these 20 or so years the basic chassis structure and suspension layout has had no significant change, although nearly all components have been replaced. The largest change was in 1988, where the original Giogiaro design replaced by Peter Steven's style. After which there is nearly one update and one new name every 2 years - Esprit SE (1989), Esprit 300 (1991), Esprit S4 (1993) and Esprit S4S (1995). Every new car has improved handling, grip and a little refinement. However, the weakest point remains to be its engine, not because it is not powerful enough, but as a four cylinder it is difficult to chase V6 and V8 for refinement.

Lotus knew the four cylinder has reached its upper limit for improvement. (if Lotus's engineers were not so competent, the engine would have been finished a lot earlier.) However, due to financial problems the V8 was delayed until 1996, which is the 20 year anniversary of the Esprit. The V8 is developed under an amazingly small budget. It is a compact design with the most common technology you can imagine : 4 valves per cylinder, twin-turbo and charger-cooler (Lotus's alternatives to costier intercooler). Displacing at 3.5 Litre, this V8 is capable of outputing 349 BHP and 296 ft-lb, sufficient to outperform Porsche 911 Carrera / RS and have a good fight with Ferrari's mighty F355.

On paper, it provides better performance than both 911 and F355, especially for acceleration, its 4.2 0-60 time is 0.4 seconds faster than F355 and a full second faster than 911. It also feels the strongest, due to the highest torque. On the other hand, slight turbo lag disappoints those admirer for Lotus' engineering excellence, especially while the 100 BHP/litre specific output is not so impressive for a turbo engine. The engine sounds least pleasing, nor rev as eager as the 40 valver of F355. Therefore it is not the best engine by any standards other than size and weight.

Nevertheless, the Esprit's chassis is an excellent example of Lotus' experience in racing. Despite the fact that it originated 20 years ago, it still provides the most accurate steering, balance and grip. At the same time, the ride is improved so that the Esprit is no longer a harsh performer.

The body shell is made of reinforced glass fibre like all Lotus', which is easy and cheap to produce in small quantities and simultaneously has the advantage of its lightness. As a result, the total weight can be kept at under 1350 kg, pretty impressive. The Cabin is always cramped, since the Esprit is one of the lowest cars in history.

To conclude the Lotus Esprit V8, I'll call it a "fast, good handling and appealing mid-engine sports car with a cramped cabin and a poor finish".

Lotus Esprite GT3
When the Esprit finally got a V8, Lotus did not drop the long-serving inlne-4. Instead, it created an entry-level Esprit with its engine reduced to 2 Litres (like the original Esprit). The power was dropped to 240 BHP and torque was reduced to 216 ft-lb as a result. Despite being less powerful, we found the lighter body delivers crisper handling while performance loss is limited - 0-60mph can still be achieved in 4.8 seconds and top speed can reach 160 mph! Most importantly, the GT3 is a lot cheaper than the V8, even cheaper than Toyota Supra turbo in UK. A true 160mph mid-engine sports car in a bargain price.

Elise
Engine: 1.8 Litre, 16V
Max Power: 118 BHP (163 BHP per tonne)
0-60: 5.5 secs
Top Speed: 124 MPH
Weight: 678 kg Unbelievable, Huh?!
Fuel Consumption: 28.94 MPG
Price: £20,950

Esprite V8
Engine: 3.5 Litre, V8, twin turbo
Max Power: 349 BHP (260 BHP per tonne)
0-60: 4.2 secs
Top Speed: 172 MPH (25.5 MPH per 1000 RPM)
Weight: 1346 kg
Fuel Economy: 21 MPG
Price: £59,995

Esprite GT3
Engine: 2 Litre, turbo
Max Power: 240 BHP
0-60: 4.8 secs
Top Speed: 159 MPH
Weight: 1240 kg