McLaren’s mighty P1 hybrid flagship looks like becoming the first hypercar ever to deliver properly on the elusive ‘F1-for-the-road’ promise that manufacturers have been making for their fastest road cars for more than a quarter century.

It has the huge V8-plus-electric power (903bhp) and ultra-high price (£866,000) that you’d expect of the spiritual successor to the illustrious McLaren F1 of 1993, but what really sets the P1 apart is its ground-breaking active aerodynamics package.

While delivering a svelte drag factor of 0.34 in ‘clean’ form, the P1 can automatically deploy a rear-mounted wing and two flaps ahead of the front wheels, in appropriate driving modes, to deliver such unprecedented levels of downforce for a road car that driving “actually gets easier as the car goes faster”. 

Even well short of its 218mph top speed, the P1 can generate 600kg of downforce, an amount equal to many Le Mans racers and about five times greater that of the recently launched McLaren MP4-12C. Its advantage over non-McLaren rivals is even greater. 

“The P1 is designed to be driven to a racing circuit with great levels of comfort and refinement,” said McLaren Automotive managing director Antony Sheriff, “and then to be used on the racing circuit where it will offer an experience matched only by purpose-built racing cars.”

The P1 uses the all-carbon chassis tub recently created as the basis for all new-era McLarens and launched with the MP4-12C. In another direct reference to F1, the new supercar has a special, race-bred ‘recipe’ for some composite components — claimed to be twice as stiff as steel — that form its core body/chassis. 

This structure has relatively few parts and weighs only 90kg, which, McLaren engineers say, is lighter than any other road car’s while delivering F1 levels of rigidity and safety. It also forms the engine airbox, roof snorkel and the roof itself, provides housings for the battery and power electronics, and shapes the aerodynamic side pods that feed air to the engine’s cooling system.

The P1 is 300mm longer than the 20-year-old F1 but only a shade wider and longer than the MP4-12C. Against its most recent compatriot, it grows 83mm (three inches) — the extra length aids the aero package — and it is 29mm (an inch) lower and 37mm (1.5 inches) wider. McLaren claims “substantially smaller” frontal area than the MP4-12C and claims that the P1 is also smaller in area than any other production sports car. 

The P1’s kerb weight is admirably low for a modern supercar, at 1400kg, (Porsche’s 918 Spider is more like 1700kg) but even it can’t match the F1, which weighed just 1140kg at the kerb.

The P1 powertrain is a hybrid partnership between a specially configured 727bhp version of McLaren’s 3.8-litre twin-turbo petrol V8, and a 176bhp McLaren-built electric motor integrated with it via a specially cast aluminium block. The two power units send their combined 903bhp (with 664lb ft of torque) through a seven-speed twin-clutch Graziano gearbox. 

The V8 carries its own special M838TQ serial number because of its special crankcase and larger turbochargers (plus other unique tweaks), which help it produce 20 per cent more power than a ‘regular’ 12C V8.

Awesome performance is to be expected, but the P1’s margin over both the featherweight F1 and the MP4-12C still comes as a shock. McLaren engineers are still deciding the final figures in fractions of seconds, but we now know that the P1 is about 0.4sec faster than the 12C to 62mph, and at least 2.5sec faster to 124mph (200km/h).

It also shaves seven or eight seconds off the 12C’s 0-186mph (300km/h) on its way to a 218mph top speed, which is a little short of the F1’s official 231mph. 

“Our aim is not necessarily to be the fastest in absolute top speed,” said Sheriff, “but to be the quickest and most rewarding series production road car on a circuit. This is the true test of a supercar’s all-round ability and a much more important technical statement.”

At the top end of the performance spectrum, the P1 uses the instant thrust of its electric motor to boost throttle response, and the instant application of its negative torque at gearshift points, to help engine revs drop quickly, making for quicker and smoother gearshifts under full power. Off throttle, the electric motor converts to a power generator, providing engine braking and replenishing battery energy. 

At the bottom of the performance envelope, the electric motor gives the car surprisingly spritely performance on its own, giving it a range approaching 20km (about 12 miles) at traffic speeds and making it suitable for the world’s growing number of zero-emissions traffic zones.

The P1 has a driver-oriented cockpit layout, under a highly aerodynamic, bubble-shaped canopy that is compared by its creators with that of a jet fighter. Or a Le Mans racer.

Although the electronic instrumentation features all the essentials and the cabin has niceties like climate control, satellite navigation and a classy sound system, equipment and switchgear are kept to a minimum and there is a general no-nonsense air about the driving position, which is individually configurable for every owner.

The doors, whose outer skins are major contributors to the P1’s aerodynamic package, use the same ‘dihedral’ opening system pioneered by the MP4-12C.

But underscoring the serious focus of the P1, the seat and steering column adjustments are manual, the seat backrests are fixed at 28deg (a change to 32deg is possible to increase helmet clearance) and the ultra-thin carbon seat shells have a minimum of padding and weigh just 10.5kg apiece. 

Carbonfibre is extensively used as a trim material (you only get carpet if you ask for it) and the interior carbon surfaces are fitted without a top layer of resin — because it saves 1.5kg. There are just two options: a heavy-duty battery charger and a set of fitted luggage.

At first, McLaren intended to build 500 P1s, pricing each one close to £866,000, but representations from potential owners (reportedly more concerned about exclusivity than price or top speed) has persuaded Ron Dennis to build just 375 copies.

"When launched we said we'd launch a new model or derivative every year. We're on track for this," said Ron Dennis. "The key word for this car is exclusivity. It really is very special." 

Dennis, who confirmed that the car had lapped the Nurburgring in less than seven minutes, commented "This, I promise, is the world's fastest car, no matter what has gone before or later today". 

The new McLaren P1 will be on sale from March and deliveries will begin before the end of the year. 

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