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Hot on the heels of the global debut of the BMW i3 is the BMW i8 plug-in hybrid sports coupe. Munich has announced that its second i model will premiere in production form at September’s IAA International Motor Show.

The Frankfurt debut comes four years after the futuristic BMW Vision EfficientDynamics Concept, the forerunner to the i8, made its first public appearance at the same show in 2009, packing a diesel-hybrid powertrain.

Two years later, also in Frankfurt, the BMW i8 concept surfaced – this time with a petrol-hybrid setup involving a turbocharged 1.5 litre three-cylinder lump (driving the rear wheels), an electric motor (driving the front wheels) and a 7.2 kWh lithium-ion battery.

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So what can we expect from the production BMW i8? For starters, its powertrain setup is similar to the i8 concept’s. The preliminary figures have been revealed to be 231 hp/320 Nm for the rear wheel-driving direct-injected internal combustion engine (mated to a six-speed auto gearbox) and 131 hp/250 Nm for the front wheel-driving electric motor (mated to a two-stage auto gearbox), resulting in a combined 357 hp and 570 Nm of twist.

Thanks to a sub-1.5 tonne kerb weight afforded in part by its carbon fibre-reinforced plastic (CFRP) Life Module passenger cell, the BMW i8 can do the century sprint in a quick 4.5 seconds and go on to hit the electronic buffers at 250 km/h.

Weight savings also come from its inner-CFRP and outer-aluminium doors (50% lighter than conventional doors), high structural rigidity allowing a reduced number of components (10% weight saving) and the use of foam plastic technology in the air-con ducts (60% weight saving, also improves acoustics by absorbing noise).

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Charge its lithium-ion battery to the fullest (3.5 hours from a household socket or about 1.5 hours from a 220V Level 2 charger) and the AWD 2+2 will be able to travel up to 35 km on electricity alone. Top speed is limited to 120 km/h in electric-only mode. Fuel economy and CO2 emissions are quoted at under 2.5 litres per 100 km and under 59 grams per km respectively.

On the move, the battery can also receive charge from the electric motor (on overrun or deceleration) and the starter-generator (fed by the internal combustion engine). The BMW i8 rides on striking 20-inch forged aluminium wheels, wrapped in 195/50 rubber up front; 215/45 out back.

Length, width and height are 4,689, 1,942 and 1,293 mm respectively, with the wheelbase measuring 2,800 mm. The drag coefficient is a low 0.26. The centre of gravity is the lowest of any current BMW model, courtesy of a low- and middle of vehicle-mounted battery pack, which Munich says also has safety benefits. Moreover, axle load distribution is a near-perfect 50:50.

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Sport mode can be engaged using the gear lever, while BMW’s Driving Experience Control offers Comfort and Eco Pro modes. These modes influence the characteristics of the engine, electric motor, suspension, throttle and gearbox as desired by the driver.

In particular, Eco Pro mode ensures electrical amenities such as air-con, seat heating and heated mirrors operate at minimum power consumption. Depending on the driving situation and vehicle status, it also automatically decides here whether to recuperate braking energy or coast with the powertrain disengaged.

On a full fuel tank and a fully charged battery, the BMW i8 manages a maximum range of over 500 km (in Comfort mode). In Eco Pro mode, this can be increased by up to 20%.

Suspension is made up of a double-track control arm front axle and a five-link rear axle. Electromechanical power steering, DSC, DTC, ABS and Dynamic Damper Control are standard fare, as are Cornering Brake Control, Dynamic Brake Control, Brake Standby, Start-Off Assistant, Fading Compensation and Brake Drying.