The mid mounted 3.8-litre twin-turbo V8 petrol engine, a variant of the M838T engine that does duty in the MP4-12C, and a ‘highly effective’ lightweight electric motor work together to give a combined output of 916PS/903 bhp and a maximum torque figure of 900Nm! McLaren points out that this additional push from the electric motor ensures instantaneous throttle response through the rev range negating any appreciable effects of turbo lag.
The M838T engine was upgraded to the current avatar to optimise cooling and durability under the higher loads. The engine block has a unique casting to incorporate the electric motor. The V8 makes 727 bhp at 7500rpm and 720Nm of torque from 4,000rpm. The lightweight electric motor, developed by the McLaren Electronics, adds 16 bhp. The electric motor produces maximum torque of 260Nm instantly from Zero and makes the engine respond like a normally aspirated mill with no turbo lag.
The electric motor is mounted directly onto the engine and power is laid on the tarmac through the dual-clutch seven-speed gearbox through the rear wheels. The electric motor also facilitates faster upshifts says McLaren. Not unlike how you would roll off the throttle in a motorcycle during a clutchless upshift, the electric motor can apply instant negative torque at the point of shift, making the engine revs drop quickly and match the engine speed for the upshift.
DRS and IPAS
DRS. That tech from Formula 1 where a moveable flap changes the aerodynamics of the car is applied here, where the rear spoiler tilts by an angle to reduce drag by 23% This is of course activate by the driver using a button on the steering wheel and is deactivated when the button is released or when the driver brakes.
IPAS is activate by the other button where the electric motor is called upon for duty, to deliver the additional 176 horses.
The 96 kg battery is also charged by KERS and when operated in the E-Mode (electric only) provides the McLaren a range of 10 km. The battery has been mounted on the underbody of the high-strength Formula 1-grade carbon fibre MonoCage chassis, which seals the unit in the vehicle without the need for additional packaging. The battery can also be stored using the plug in charger stowed in the luggage compartment.