Lotus was at a low ebb in the early 1990s. Colin Chapman was no longer around to pull Lotus out of a hole with his fabled stroke of genius. The Formula I efforts of Team Lotus were in technical and sponsorship trouble and Lotus withdrew from the Formula I Championship at the end of the 1994 season. The front wheel drive Series 2 Elan and aged Esprit were not selling up to expectations. Lotus was about to be sold by GM and the prospective buyers were only interested in the engineering side of the company.

Enter Romano Artioli, head of Bugatti Industries, to buy Lotus. Without him there most likely wouldn't have been any more Lotus cars. The Elise was his project - and the car was named after his grand-daughter. The Elise was to be the most technologically advanced, no-frills, afforable sports car in the world. It had to be classic Lotus. Spectacular handling and performance - achieved through innovative design technologies - were to be its hallmarks.

The current production car, the second-generation Elan, would be out of production in two years, after its Isuzu engine supply had been exhausted. The new Elise represented a daunting challenge, both technically and time-wise, but one that Lotus, under Chapman, had achieved several times before. Could they do it without Chapman?

Initially, there was the task of defining what type of chassis was to be built. The classical multi-tube space frame and the backbone chassis were definitely out, as this car was to be a new design. On one extreme there were the flimsy frames of touring cars made into pseudo-sports cars - like the original Mustang, which had been adapted from the Ford Falcon. At the other extreme was the modern group C sports racer with a very light and highly torsionally-rigid composite tub chassis.

Steel was eliminated as the chassis construction material because of its weight. It was decided that the chassis would be made of aluminum. Tooling up for extruding of aluminum can be a hundred times less expensive than that for a die to press steel parts. The design of the chassis would possibly be some type of tub structure. The target for torsional stiffness was 10,000 Nm/degree of twist (7400 ft-lb) with a chassis weight of 70 Kg (154 lb). The car weight would be around 700 Kg (1540 lb). This target for the chassis is three times stiffer than the 3000 lb Esprit coupe, and for a lightweight, open-top car this level of stiffness would be bordering on the phenomenal.

The chassis design geometry finally arrived at consisted of two tubes of rectangular cross-section on each side of the car. These were connected transversely at the front and rear by torque boxes and a flat panel underneath. There is a crash structure attached to the front of the chassis and a crumple zone at the rear. The engine and transaxle are held in a steel subframe which bolts to the chassis at the rear. Lotus classified the chassis as an aluminum monocoque tub.

To build the chassis Lotus brought in the Automotive Structures Division of the Scandinavian company Hydro-Aluminium, specialists in aluminum extrusions, aluminum bonding and welding. Bonding aluminum panel areas, as opposed to welding them along a seam, would keep the chassis weight down. A bonded panel could be 2.5mm thick, while a welded panel would have to be 6mm thick.

Although bonding can absorb more stress than welds, when the limit is reached, the joined area collapses or peels apart. At the limit, welds begin to elongate and give up slowly. Lotus wanted to use bonding. To resolve this problem Lotus figured out that if Ejot self-threading fasteners were fixed to the joined aluminum panels, the joints would stay together even if the bonding failed. This un-Chapman-esque redundancy marks a mainstream trend at Lotus. The bond is created by an epoxy adhesive applied after the chassis has been placed in the jig and secured by the Ejot fasteners. The bond is cured in an oven for 4 hours.

The as-produced chassis weighs 150 lbs and, with roll bar and body shells attached, exhibits a torsional stiffness of 11,000 Nm/degree of twist (8100 ft-lb). It is designed, with door beams, to take a 10-ton force from any direction, and suffer no chassis damage in a 30-mph frontal crash. The roll bar is massive and is designed to completely protect the car's occupants in the event of a roll over. The Lotus Elise chassis represents the leading edge in production car chassis design.

The aluminum underbody is completely flat for aerodynamics. Flat-bottom cars maintain laminar flow of air underneath, which minimizes lift and drag from that area of the car. There are two NACA ducts on the undertray to diffuse air into the sump and the gearbox.

The body is composed of two fibreglass clamshells which are bolted to the chassis and two side panels which contain the door openings. Chapman's patented vacuum assisted resin injection process is used for the side panels and door moldings. The clamshells containing numerous joined sections are laid up by hand.

The styling is classic Lotus - curvaceous with low nose, high fenders, inverted airplane wing silhouette as can be seen in the previous Lotuses like the Elite, 11 and 19. There is minimum body overhang to attain the longest possible wheelbase on such a small car. Some have accused the looks as being retro, but the car had to be recognizable as a Lotus and different from all other cars. It's an evolution of the Lotus shape just as the current Jaguars, Porsches and Ferraris are of their shapes. The photos below show three stages in the design of the Elise body shape.

The suspension is double wishbones with single coil springs/mono-tube dampers all around. There is a front anti-sway bar. The suspension uprights are extruded aluminum as are the brake, clutch and gas pedals. The suspension is completely adjustable. The brakes are 11" aluminum-silicon matrix composite, lightweight and good at conducting heat away from the disks (as opposed to steel disks which are heat absorbers but not good conductors).

The engine is the aluminum block/head 1.8 liter DOHC Rover K-Series with (at basic tune) 118 hp @5500 rpm and 122 ft-lb of torque @3000 rpm. 0-60 is 5.5 seconds and 0-100 is 18 seconds. The Sport 190 developes 190 hp @7500 rpm, 140 ft-lb of torque @5500 rpm. 0-60 is 4.4 seconds and 0-100 is 13.2 seconds.

Series 1 Elise	Series 2 Elise