McLaren has been dispensing nuggets of information about its new P1 supercar, which will make its debut in production form at the Geneva International Motor Show, a bit at a time.
The latest revelation about the latest McLaren exotic is that it will be a plug-in hybrid.
A mid-mounted 3.8-litre twin-turbo V-8 gasoline engine will combine with an efficient electric motor for a combined output of 903 horsepower, with maximum torque of 664 lb-ft available from 4000 rpm up.
The lightweight electric motor, developed by McLaren Electronics, produces 176 horsepower and generates 192 lb-ft of torque instantly from a standstill. It is unique to the P1.
The electric motor is mounted directly onto the engine and drive from both is channelled through a dual-clutch seven-speed gearbox to the rear wheels.
McLaren says the combination of the two powerplants will provide instantaneous throttle response throughout the rev range, similar to a naturally aspirated engine, as well as excellent day-to-day driveability.
The McLaren-developed IPAS ‘boost’ system provides up to 176 horsepower instantly from the electric motor, activated by a button on the steering wheel.
A similar button engages the DRS, reducing the rear wing angle sufficiently to lower drag by 23%. The system immediately deactivates when the button is released, or if the driver touches the brake pedal.
The e-motor, which will permit city driving in electric mode only for up to 10 km, also enables faster upshifts by applying instant negative torque to make the engine revs drop quickly to the speed required for the next gear.
When off-throttle, the electric motor provides additional drag torque, recovering energy to the battery that would otherwise be lost to the brakes.
Energy is stored in a lightweight battery pack that priorizes power delivery over storage capacity. It is said to have greater power density than any other automotive battery pack on sale today.
The battery's mass is just 96 kg, and it is mounted onto the underbody of the high-strength Formula 1-grade carbon fibre MonoCage chassis, which seals the unit in the vehicle, thus avoiding the added weight of any special battery packaging.
A complex cooling system keeps coolant flow balanced so each cell is maintained at the same temperature across the entire battery pack.
In addition to on-board charging via the engine, the P1's battery can be charged via a plug-in charger that can fully replenish the charge in two hours. The plug-in charger can be stored in the luggage compartment.
Further details of the McLaren P1 will be released between now and its debut at the Geneva auto show in March.