McLaren P1: full details revealed

The new McLaren P1 ‘ultimate supercar’ will have a power-to-weight ratio of over 600bhp per tonne when it goes on sale in late 2013, suggesting, if the P1 is lighter than the MP4-12C, a total output of around 720bhp.

The company will not release any information about the drivetrain, interior or specific performance, but it the engine is expected to receive some kind of hybrid assistance. 

Making its public debut today at the Paris motor show, the company says the P1 takes its ‘technological and spiritual inspiration’ from the company’s Racing division and has "one simple goal….to be the best driver’s car in the world on road and track." The concept P1 shown at Paris has no interior, but the exterior is described as "more than 95 percent" of the the final production car. 

It is claimed  the P1 can generate 600kg of downforce at a pace "well below" the car’s maximum speed, a figure that is around five time more than the is generated by the current 12C road car and around the same as the 12C GT3 car. Programme director Paul Mackenzie says that the P1 was designed to feel like a "proper racing car" at the push of a button, which could then be driven home in "great comfort and refinement."

Autocar has learnt the P1 will have three different ride-height modes, with the lowest for track work. This latter track mode ensures that the car’s side skirts and rear diffuser work properly but also mean that the diffuser’s carbon fibre strakes are just a couple of inches above the track surface.

The P1 uses a different core carbon fibre structure - dubbed Mono-Cage - to the 12C, which incorporates a carbon roll-bar over the cabin. The roll-bar is exposed on the outside of the vehicle and also incorporates an air scoop which feeds 'clean' (aerodynamically unruffled) air into the engine bay. 

The car’s basic 'jellymould' engineering package was generated primarily by aerodynamic concerns and the desire the shrink the exterior to an absolute minimum. This package was used as the basis for three design proposals, from which this final design was chosen. 

The final shape is described as more of a joint engineering/design production than a styling exercise, but Frank Stephenson says that the P1 was intended to look like a "Le Mans racer...with a long, low body, long rear deck and open mesh styling to put the mechanicals on view and help cooling" .

The car’s external appearance is driven by two main requirements: the need to get air in and around the car and the need to get heat out. The most striking thing about the P1 is the huge air intakes that have been accommodated in the doors. As well as the large intake cut into the door skin, there is second intake cut into the top of the door skin, that channels air into the rear radiators through the door structure itself.