Lotus Evora, 2010
The first all-new Lotus since the iconic Lotus Elise made its debut in 1995, The Lotus Evora enters the sports car market as currently the world's only mid-engined 2+2. Powered by a Lotus-tuned 3.5-litre V6 engine producing 280 PS, and weighing just 1350 kg (prototype specification), the Lotus Evora promises breathtaking performance. During preliminary testing around the famous Nürburgring, the Lotus chassis engineers report that it is extremely agile and great fun to drive - even when clad with the full development disguise that hid the beautiful lines from the prying motor-industry paparazzi.
In addition to its excellent performance and exemplary handling, the Lotus Evora offers a more refined ownership experience than Lotus's existing smaller four-cylinder models. Its elegantly styled cabin is elegantly trimmed and its equipment list includes contemporary features such as an advanced touch-screen multi-media system and electric power-fold door mirrors.
THE LOTUS EVORA IN DETAIL
The Style or function? Have both... Designed 'in-house' by Lotus Design, the sleek and athletic form uses fluid forms and crisp surfaces to communicate velocity, agility and sophistication. Low and wide with modern cab forward proportions, muscular rear haunches and function optimised hip air intakes this is clearly a serious mid engined sportscar that skilfully hides the practicality of its two plus two capability.
Ingress and egress, for example, dictated a minimal "step-over" to get into the Lotus Evora. We simply cut away the surface under the door and created a unique and dramatic piece of sculpture that enhances the stance of the car as well as its useability.
Elsewhere, aerodynamic considerations for drag, down force and cooling had significant but positive influence on the overall form and details such as air intakes. A desire to create balanced down force, that increases cornering performance, led to the adoption of, the now, "signature" top exit radiator vent, race car inspired diffuser and "floating rear wing". Drag limitation, drove the dramatic tear-dropped cabin layout and the curvaceous plan view has given the car a more muscular rear shoulder and conveys a level of sophistication appropriate to this market segment.
This inherent understanding of the relationship between the technical and the aesthetic paid dividends the first time a full-scale model of the Lotus Evora was wind-tunnel tested - only minimal adjustments were required to the car's aerodynamic package to meet the targets for downforce and stability.
The view from the rear three-quarters is just as striking and the one that many will become familiar with as the car passes them on the road. The tapered cabin, diffuser, floating wing, centrally mounted twin tailpipes and distinctive engine bay vents all combine to create a completely unique look.
The design language of the interior reflects that of the exterior - simple, fluid surfaces, soft forms and crisp feature lines wrap around the cabin cosseting the occupants. Unlike recent Lotus products that use a race car inspired, technical minimalism, the Lotus Evora employs a softer approach that utilises premium quality materials and finishes to create a contemporary but luxurious ambience that is unique to Lotus products.
Focused courtesy lighting is used throughout the interior, giving a spectacular illuminated feel to the sculpture design feature of the cabin.
Easy in, easy out
With the Elise and its derivatives, the no-compromise character of the car makes getting in and out across a wide sill and through a comparatively narrow door/window aperture part of the charm of ownership. For the Lotus Evora and its remit for the serious daily driver, and to attract newcomers to the Lotus brand, greater convenience and practicality is provided.
As a consequence the sill is now lower and slimmer (80mm wide compared with 100mm in the Elise), and the whole door aperture taller. The doors open wider than on the Elise and its siblings, while the height of the front seat is raised by 65mm.
But while the Lotus Evora is undeniably more 'lifestyle' in respect of its everyday practicality, once you're seated behind its flat-bottomed steering wheel, it feels every bit as exotic and sporting as you would expect a Lotus to be.
The chassis: Production Low Volume Versatile Vehicle Architecture
The Lotus Evora's chassis is an evolution of the Versatile Vehicle Architecture (VVA) from the Lotus APX concept vehicle previously showcased at the Geneva Motorshow, and allows for the development of a range of vehicles up to a gross vehicle weight of 1,900 kg. This architecture has been designed to be more applicable to mid-volume applications by utilising our low capital investment manufacturing processes. The Lotus Evora structure progresses the Lotus 'bonded and riveted' technology used in the Elise family of vehicles with unique extrusions and folded panels, whilst providing contemporary ease of ingress/egress, build modularity and improved, lower cost repairs.
The Low Volume VVA architecture has been designed so that it can be extended in width, length and height. The strength and stiffness of the low volume VVA chassis can be modified cost effectively by varying the wall thickness of the extrusions, without altering the exterior dimensions. The ability to lengthen or shorten extrusions with the option to tailor the chassis stiffness, vastly increases the number of vehicles that can be developed from this vehicle architecture. Front and mid engine installations have been considered, as well as hybrid and Electric Vehicle (EV) applications.
The Lotus Evora employs a composite roof as a stressed structural member to give an exceptional vehicle stiffness of 26,000 Nm per degree, thanks in part to the seatbelt anchorage frame's secondary function as a roll over structure, and partly because the high-tech composite body panels are stressed items. However, despite this high stiffness, the complete chassis and modules weight just 200 kg (prototype weight), helping to keep the weight of the whole car to just 1350 kg (prototype weight).
The Suspended & animated
The Lotus Evora suspension wishbones are forged from aluminium to reduce the unsprung mass. These are similar in weight, and stiffer than the steel items found on the much smaller Elise, Exige and Europa vehicles, and have a far higher vehicle weight capacity. They are attached to the front and rear modules via bespoke bushes. The Lotus Evora will use Bilstein high performance dampers and Eibach springs with unique dual path top mounts for optimised vehicle refinement. Hydraulically assisted power steering is provided by a Lotus tuned TRW steering rack.
All in all, the Lotus Evora delivers. It has incredible Lotus handling and provides unsurpassable driving pleasure. In fact, word from the ride and handling team is that the new car is likely to become a class standard-setter for speed and agility.
Stop right now... Vented and cross-drilled brake discs - massive 350mm items on the front and 332mm at the rear - and high performance bespoke Lotus AP Racing 4 pot callipers ensure impressive stopping power.
Everyone connected with the brake testing programme, conducted on the punishing corners, climbs and descents of the Nürburgring, has described the brakes as 'phenomenal' with excellent thermal performance and outstanding feel even after extended sessions of extreme use.
Part of that testing programme was to finalise settings for the ABS system being developed in conjunction with Bosch. The system is set to very high thresholds and operates so progressively that drivers are often unaware that they have actually triggered the ABS.
Safe. Fun. Lotus Traction Control
The Switchable Lotus Traction Control (LTC) system has been developed simultaneously with the ABS and works through the engine management system to reduce power when required to maintain traction. Unlike many traction control systems, LTC has been tuned to complement the skills of the driver without taking over. The Lotus LTC is active above 5 mph (8 km/h) and operates much more quickly than many brake based systems. The system can be deactivated completely, giving no traction control intervention.
Keeping a grip - 18 inch at the front, 19 inch at the rear
Tyre choice is a vital component in the handling performance of every Lotus and for the Lotus Evora, Yokohama was chosen as development partner.
Lotus's long-term relationship with Yokohama was swiftly rewarded during development when initially the front tyre size did not generate the Lotus required lateral grip, the Japanese grip gurus went away and developed bespoke tyres especially for the Lotus Evora - a 225/40 ZR18 at the front and larger diameter; 255/35 ZR19 at the rear. Both have carcass construction and a rubber compound unique to Lotus and are identified by the letters 'LTS' on the sidewalls.
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