Lotus regards its Evora 400, to be unveiled at the 2015 Geneva Motor Show this week, as virtually a new model.

Although the established Evora aesthetic signature and configuration remains, more than two-thirds of the outgoing version has been re-engineered, lightened, and redesigned inside and out, in a program to give it full supercar status as Lotus's most powerful and fastest ever production car.

It should be good news for Lotus aficionados and for production figures alike. Since the Evora’s first appearance in 2009 and despite subsequent changes—including the addition of a supercharged engine for the S version in 2010 and a major revision to raise quality in 2012—it is a model that never quite fulfilled its apparent promise but that given the opportunity and the investment, could have been a whole lot better.

With the 400, that opportunity has apparently been fulfilled. Jean-Marc Gales, who became Group Lotus CEO in May 2014, said: “It delivers supercar looks allied to supercar performance.”

It is certainly more powerful. Its 3.5-L mid-mounted Toyota V6 engine delivers 400 bhp (298 kW) at 7000 rpm to support the model’s name, and it gives the car a 300-km/h (186-mph) top speed, making it the fastest-ever production Lotus.

The car delivers on the practical side, too, with major changes to its structure to provide a level of access to the cockpit that will no longer require an athletic level of body elasticity. Once inside, occupants will appreciate a cabin that takes the car further into the luxury category that it entered in 2012. Despite this and other upgrades, curb mass has been trimmed by a modest but useful 22 kg (49 lb) to 1415 kg (3120 lb).

Within the Lotus Group, the emphasis is now very much on enhancing Lotus Cars (production of all Lotus models is slated to rise from 45 units per week to 70 by Q3 2015), while Lotus Engineering, long established as a broad-based and respected automotive consultancy and development business, will give its client list a narrower but sharper focus.

Lotus' emphasis that the Evora is in the supercar class is supported by its performance figures. As well as its high top speed, 0-100 km/h (0-62 mph) time is 4.2 s. Maximum torque is 410 N·m (302 lb·ft) between 3500 and 6500 rpm. CO2 emissions are down slightly.

The engine’s high power output is up 16% from a previous 345 hp (257 kW) via an Edelbrock supercharger, bringing efficiency improvements including a volumetric capacity rise from 1.32 to 1.74 L/rpm. A new charge cooler and engine management modifications have been applied. Exhaust system changes include driver-activated free flow to reduce backpressure bringing—important for any sports car—a distinct aural signature enhanced by a big-bore central tailpipe, something the original Evora lacked.

The engine has received new mounts, saving 5.6 kg (12.3 lb), and a revised subframe, providing better dynamics. Transmission choice is six-speed manual or auto. The manual gets a lower inertia flywheel; the auto has a different shift pattern.

Chassis changes include a Torsen-type LSD (limited slip differential) as standard for the manual Evora. Traction slip thresholds in Drive, Sport, and Race modes are driver selectable, the latter two also sharpening throttle pedal response. Revised spring and damper settings are used. Brake specification has been improved, the brakes being two-piece, cross-drilled, and ventilated—and bigger at 370 x 32 mm (14.6 x 1.3 in) front and 350 x 30 mm (13.8 x 1.2 in) rear. Forged aluminum wheels, 19 in front and 20 in rear, save 3.3 kg (7.3 lb).

The Evora continues to use an aluminum bonded and extruded chassis. This has been redesigned to improve occupant access: sills are narrowed by 43 mm (1.7 in) and lowered by 56 mm (2.2 in), without a loss in the car’s 27,000 N·m (19,900 lb·ft) per degree torsional stiffness. Narrower door inner panels also make for better access.

The Evora 400 gets new front seats, each saving 3 kg (6.6 lb). To give the car perceived added luxury, trim materials include Alcantara or Scottish leather, each with specific detailing. A new HVAC system is fitted. Switchgear haptics are better, and an engine stop-start button is now fitted.

Aerodynamics are a very significant part of any supercar and, although the Evora’s Cd is up slightly from 0.35 to 0.33—mainly the result of the greater cooling needs of the car’s more powerful V6—downforce is slightly improved: 12 vs 6 kg (26 vs 13 lb) front and 20 vs 10 kg (44 vs 22 lb) rear at 242 km/h (150 mph). Aerodynamic aids include a flat floor, rear diffuser, and three-element rear wing. The Evora’s overall length is increased by 35 mm (1.4 in) to 4394 mm (173.0 in).

Head of Lotus Cars’ design, Russell Carr, stressed the need to make changes to the Evora’s looks but explained: “We were also sure that to alter greatly the profile of the recognizable mid-engined Evora design would have been wrong intrinsically.”

Front and rear ends do get new looks, though.

Carr explained that the use of an integrated digital design process allowed computer data to be translated rapidly into physical models using state-of-the-art milling and 3D printing techniques.

The Evora is expected to remain Lotus’s main product “for many years” (others are the Elise and Exige), with more derivatives in the pipeline, stated Gales. (In September 2010, a much wider model range was envisaged by previous management, but those plans have been rethought.)