Like the BMW i8 Coupe, the new BMW i8 Roadster is based on the LifeDrive vehicle architecture with aluminium chassis and carbon - fibre - reinforced plastic (CFRP ) passenger cell. The further optimized BMW eDrive technology employed in both models comprises a high - voltage battery with significantly expanded cell capacity and energy content, and an electric motor generating a higher peak output. The result is a noticeable increase in dynamic performance , operating range and the amount of driving possible using purely the electric drive system.
The internal combustion engine has also undergone further optimisation to ready it for the new BMW i8 Coupe and new BMW i8 Roadster. The three-cylinder unit extracts maximum output of 231 horsepower (170 kW) from its displacement of just 1.5 litres, along with peak torque of 320 Nm (236 lb-ft). In the process, it generates an even sportier sound track. A particulate filter is now fitted to further reduce emissions by absorbing the particulate matter contained in the exhaust gases.
The system output produced by the electric motor and engine acting in unison is now 374 horsepower (275 kW). The new BMW i8 Coupe accelerates from 0 to 100 km/h (0-62mph) in 4.4 seconds, while the new BMW i8 Roadster takes a tick longer with a time of 4.6 seconds. Both models have an electronically limited top speed of 250 km/h (155 mph).
