UK, Nov 2017 - The BMW i8 is the sports car of the future in the showrooms of today. The 2+2 seater has been a technological pioneer and the world’s best-selling hybrid sports car since it arrived in 2014.
Now, the allure of sustainable driving pleasure is poised to enter another new dimension. The all new i8 Roadster takes the combination of emission-free and high-performance and adds open-top thrills. It is unique in offering such performance and silent acceleration with the pure sensation of roof-down driving.
Following the world premiere of the i8 Roadster at the Los Angeles Auto Show 2017, the order book will open in January 2018. The Roadster will be joined in showrooms by the mid-life update of the i8 Coupé, with both models based on the LifeDrive vehicle architecture purpose-built and designed for BMW i cars. The aluminium ‘Drive’ module brings together the powertrain, high-voltage battery, suspension, crash system and structural functions, while the ‘Life’ module takes the form of a carbon-fibre reinforced plastic (CFRP) passenger cell, unique to the segment.
The i8 Roadster benefits from lightweight construction, complete with a low centre of gravity and even weight distribution. The aerodynamic exterior – with model-specific dihedral doors – is a fine exponent of the signature BMW i design language.
The BMW i8 Roadster: two-seater with electrically operated soft-top roof and additional on-board stowage space.
Passengers inside the i8 Roadster will look up to find either the open sky or a high-quality, all-season fabric soft-top with high-level soundproofing. All-electric operation ensures the roof opens or closes in an almost silent hush, within 16 seconds and while travelling at up to 31mph.
The i8 Roadster is unique in offering a fabric soft-top which stows into a perpendicular position in the rear when opened, therefore taking up very little space. The three segments of the roof fold vertically in a Z-shape, leaving an additional 100 litres of storage space between the roof box and the seats, on top of the 88 litres of cargo space in the rear compartment.
Opening the roof raises the rear window automatically by around 30mm, reducing air turbulence inside the cabin and ensuring passengers can enjoy the pleasure of open-top driving with minimal disturbance. The driver can adjust the height of the window at the touch of a button and control airflow as desired.
Intelligent lightweight design and innovative production technology also play a key role in the car’s construction. For example, aluminum elements connecting the roof with the body of the car are produced via a new 3D printing process. This manufacturing method breaks new ground in the industry and allows the parts to be produced in a geometric form, which would not be possible using conventional casting techniques.
Optimised BMW eDrive technology: more power, increased range; electric driving experience raised another notch.
BMW’s rigorously developed eDrive technology powers both the i8 Roadster and Coupé. The number of driving situations where the electric motor is solely responsible for powering the car has been significantly increased. By contrast, the combustion engine is only brought into play when accelerating hard, and is switched off again more frequently with a measured driving style.
Underpinning its improved emission-free range is an updated version of the i8’s lithium-ion battery. The high-voltage unit is located centrally under the car, and its cell capacity is increased from 20 to 34Ah. All of which means the motor has more energy at its disposal. Plus, the cell configuration allows a 12hp increase in peak output to 143hp.
The improved technology means the i8 Roadster can cover up to 33 miles with zero emissions, while the i8 Coupé can achieve up to 34 miles, broadening the reach of all-electric mobility well beyond the city limits.
Groundbreaking lightweight design, systematic improvement of aerodynamics and advanced plug-in hybrid technology are the mainstays of a trailblazing concept turned reality.
The framework was provided by the new LifeDrive vehicle architecture for BMW i models, whose horizontally split structure comprising an aluminium chassis and a CFRP passenger cell offers an exceptional degree of design freedom. The visionary styling of the i8 Coupé therefore succeeds in expressing not just the car’s dynamic performance, but also its outstanding efficiency. The new i8 Roadster translates the BMW i design language to another vehicle concept, fusing the proportions of the i8 with signature roadster features to give it a character all of its own.
The proportions, lines and surface design mark out the i8 Coupé and the i8 Roadster as belonging to a new breed of sports car. A flat bonnet, visible aerodynamics, short overhangs, a long wheelbase, broad track and an elongated roofline create an aura of dynamism, lightness and efficiency.
The i8 Roadster’s broad roof retracts fully into the rear end, lending greater emphasis to the car’s low-slung silhouette. The CFRP passenger cell’s robust structure means the soft-top could be designed to be wide, creating a large view to the sky. The rear window extends into a comfort position and acts as a windbreak.
The C-pillars are adorned with beautifully made model-specific badges bearing the inscription “Roadster”. A similar logo can be found on the tail of the sporty two-seater.
New exterior paint finishes, exclusive light-alloy wheels.
The design cues common to both the i8 Coupé and Roadster include dihedral doors that open forwards and upwards as well as optimised aerodynamics. The low bonnet, the BMW kidney grille, air flap control system, Air Curtains in the front apron, sealed underbody, contoured side skirts, “stream flow” lines of the car’s flanks, and air ducts between the rear lights and roof frame allow the air to be channeled extremely effectively. The flow of cooling air at the front has now been rerouted, instead of flowing out through the outlet in the bonnet the air escapes at the sides of the car near the wheel arches and into the underbody. This ensures a pleasant cabin temperature is maintained at all times, especially when travelling with the roof down.
E-Copper metallic and Donington Grey metallic have been added to the choice of exterior paint finishes available. Both are combined with accents in Frozen Grey metallic.
The i8 Roadster and Coupe are equipped with exclusive 20-inch light-alloy wheels in a W-spoke design. Intelligent lightweight design also makes an impact here, with each wheel weighing around one kilogram less than the lightest wheels previously available for the i8. Customers can also choose from another three light-alloy wheel variants with the same dimensions.
Innovative interior design in a range of new looks.
The progressive style of the i8 Coupé and Roadster shines through clearly in the interior design. Standard specification for both includes a sports steering wheel and multi-functional instrument display, plus Carpo interior trim comprising full-leather upholstery in Ivory White for the Coupé and Ivory White/Black for the Roadster. Carpo trim can alternatively be specified in dark Amido for both models and there is also the option of Halo interior trim featuring cloth/leather upholstery in a Dalbergia colour scheme.
A new high-line ‘Accaro’ interior trim, featuring cloth/leather upholstery in an Amido/E-Copper colour scheme is also a new option.
Powertrain, chassis and body.
The new BMW i8 Coupé and new BMW i8 Roadster are powered by a hybrid synchronous electric motor and a three-cylinder petrol engine with BMW TwinPower Turbo technology. The engine’s power is fed to the rear wheels through a six-speed Steptronic transmission, while the electric motor propels the front wheels via a two-speed automatic gearbox. The end result is a hybrid-specific all-wheel-drive system that glues the car to the road.
Further refined high-voltage battery, electric motor with more power for superior driving pleasure in all-electric mode.
Continual development has enhanced the performance offered by BMW’s eDrive technology. The energy capacity of the latest version of the i8’s lithium-ion battery has increased from 20Ah to 34Ah and gross energy capacity from 7.1kWh to 11.6kWh (net energy capacity: 9.4kWh). This advance is down to advances made in battery cell technology, which in turn stem from the BMW Group’s ever-increasing expertise in the field of electrical energy storage.
These extra energy reserves have made it possible to raise the electric motor’s peak output by 12hp to 143hp. In typical electric motor fashion, it generates its maximum torque of 250Nm from rest, which means it is ideally equipped to deliver razor-sharp responses to the slightest movement of the accelerator. The electric motor developed by the BMW Group also stands out with its consistent power delivery up to high revs.
The battery cells’ higher capacity means that the proportion of all-electric driving can be increased substantially, even in hybrid mode. With the default driving mode engaged, both the new BMW i8 Coupé and new BMW i8 Roadster are capable of pulling away and reaching speeds of up to 65mph purely on the electric motor’s power, making it possible to drive with zero emissions not just in town, but on country roads as well. And if the eDrive button is pressed, the all-electric threshold of both models is increased further to 75mph.
The new high-voltage battery benefits the electric range of the two plug-in hybrid sports cars too. In the EU test cycle, the new BMW i8 Coupé achieves a maximum range of 34 miles – around 50 per cent more than before – while the figure for the new BMW i8 Roadster is 33 miles.
Three-cylinder petrol engine with improved sound and lower emissions.
The i8’s combustion engine has also undergone further improvements. The turbocharged three-cylinder unit featuring direct injection and VALVETRONIC variable valve timing extracts a maximum output of 231hp from its displacement of just 1.5-litres, plus peak torque of 320Nm. It is pleasantly refined and generates a distinctive soundtrack that now has an even sportier note when its power reserves are called upon. The engine also runs more cleanly, as it now comes equipped with a particulate filter as standard that effectively absorbs all the particulate matter contained in the exhaust gases.
The system output produced by the electric motor and engine acting in unison has increased to 374hp. The new BMW i8 Coupé accelerates from zero to 62mph in 4.4 seconds, while the new i8 Roadster takes 4.6 seconds. Both models have an electronically limited top speed of 155mph.
Combined fuel consumption, as calculated in the EU test cycle for plug-in hybrid vehicles, stands at 149.8mpg for the BMW i8 Coupé and 134.5mpg for the BMW i8 Roadster – which equates to petrol CO2 emissions of 42 and 46g/km respectively – plus 14.0kWh of electricity for the BMW i8 Coupé and 14.5kWh for the BMW i8 Roadster. In everyday driving, both models return fuel consumption and emissions figures that undercut those for conventionally powered sports cars with similar outputs by around 50 per cent. A typical commute through city traffic and along country roads can be negotiated with fuel consumption of over 56mpg when using both drive units. On long-distance journeys with prolonged sections of country and motorway driving, the intelligent energy management ensures that average economy betters 40mpg.