A revealing concept and a host of teaser images have given us an idea of what to expect, but until now, the British carmaker has been tight-lipped on engine details.
In the existing 12C supercar, the small but powerful V8 delivers a hefty 460kW. That isn't enough go-juice to propel a hypercar however, so McLaren has boosted the engine's output to 542kW and bolted an electric motor directly to its side.
Combined, the system delivers a massive 673kW and 900Nm of torque.
A high-density 96kg battery pack provides energy for the electric motor, and all power is sent to the rear wheels only through a seven-speed dual-clutch transmission.
McLaren says the P1 will emit less than 200g/km in carbon emissions, and an all-electric driving mode will allow around 10km of petrol-free driving.
A Kinetic Energy Recovery System will feature, along with a version of the Drag Reduction System (DRS) that has also starred on the F1 track.
For the P1, the DRS system will reduce the rear wing's angle by 23 percent, activated at the push of a button and deactivate either when the button is released, or the brake pedal is engaged.
The P1’s structure will be based on an evolution of the 12C’s MonoCell carbon fibre/aluminium tub dubbed ‘MonoCage’, with the P1’s tub integrating side and roof air intakes and increased attention to passenger safety.
Production of the P1 is scheduled to begin later this year.