The McLaren P1™ is very much an engineering-led design, as is the McLaren way. Form follows function. Nothing is superfluous. Everything is designed for a reason, as with a Formula 1 car.
The mid-engine two-seater design reflects the aerodynamic requirements needed to meet the ambitious downforce target. But there was also clearly a desire to make a very beautiful and striking ‘supersports’ car.
Says Chief Design Engineer Dan Parry-Williams: ‘The McLaren P1™ reflects the brand’s core values. It celebrates aerodynamics, great packaging and light weight, and is all about innovative technology. At the very beginning, we sought to develop a car that you could drive to a racing circuit, then press a button and race it.
‘The priority was high-speed performance matched with tremendous composure, which would come mostly from the state-of-the-art aerodynamics. We wanted a car that was connected and predictable at any speed.’
LIGHT AND AGILE
The design team worked to a brief of ‘light and agile’. The design had to be ‘shrink wrapped’ around the mechanicals, making the car as compact and lightweight as possible. Even the number of body panels – all made from lightweight carbon fibre – was kept to a minimum. The strong carbon construction means they can ‘multi-task’ – acting as aero-honed ducts and load-bearing supports. They are intricately shaped yet superbly finished, helped by their strong carbon construction. There are only five main panels: front clamshell, front bonnet, rear clamshell and the doors.
The McLaren P1™ sits extremely low (1,138mm height in Race mode) with a substantially smaller frontal area than the (already small) 12C, and smaller than any other series production super sports car. Cd is just 0.34 – very low considering the enormous levels of downforce.
The incredibly low rear and pronounced rear haunches highlight the ‘shrink-wrapped’ design and efficient packaging. Importantly, the design gives superb airflow to the large adjustable rear wing. The shape of the whole body, and the sculpted doors in particular, are clearly shaped by the path of the air flowing over and around the car.
The ‘shrink-wrapped’ design concept, including the low rear deck, rear wing, inlets and outlets, and teardrop-shaped glass canopy was initially produced as a three-dimensional surface model by Chief Design Engineer Parry-Williams, and his team, which defined all of the critical packaging and aerodynamic requirements. This was evolved from current Le Mans car principles. This preliminary surfaces were developed and refined throughout the Concept Design process to create the final styled shape, while still respecting all of the aerodynamic, cooling, packaging and manufacturing requirements. During this phase, details of systems such as the roof snorkel engine air intake, radiator air intake systems, front underbody aerodynamics, ‘low temperature’ cooling system and engine bay cooling were all worked out in detail. This involved extremely intensive detail engineering design, aerodynamic CFD simulation for aero efficiency and cooling.
Parry-Williams explains: “An early mule prototype was built during this phase to prove out the simulation results, while the design was still fluid. Developing the design to this point before the styling process was essential in order to achieve the incredible compactness, aerodynamic performance and overall design integrity.”
Working closely with Parry-Williams, Design Director Frank Stephenson wanted a car that was ‘striking but also functional, a real statement of intent. I wanted a genuinely beautiful and dramatically honest “supersports” car, in keeping with the heritage of McLaren but also at the forefront of automotive design.
‘The engineering priority was unmatched aerodynamic performance. My role as a designer was to make it look dramatic and beautiful.
‘I wanted it to look like a Le Mans racer with that low body, long rear deck and open mesh rear styling to put the mechanicals on view and to help cooling,’ says Stephenson. ‘Plus there is the most aggressive rear diffuser ever seen on a road car. Like everything on the McLaren P1™, it’s there for a good reason.’
FIGHTER JET CANOPY
The glasshouse on the McLaren P1™ was inspired by the canopies of fighter jets, which creates a sense of flying. As with the 12C, the windscreen is deeper than it is wide, which gives a feeling inside of lightness and airiness in the cabin. The front cowl is especially low. Good visibility has always been a McLaren mantra. The two glass solar-reflecting panels above the cockpit further improve visibility and airiness, while the teardrop shaped canopy optimises the airflow to the rear wing.
The ‘hammerhead’ style nose looks dramatic, giving the car a low and wide stance but, as with everything on the car, it also serves an important functional purpose. The design serves to direct airflow to two front mounted low temperature radiators, which cool the petrol engine’s turbocharged air and the IPAS powertrain’s electrical system. The narrow LED headlamps, shaped in the style of the McLaren ‘speed marque’, give superb illumination but are also very space efficient, optimising the frontal area that can be used for cooling.
The distinctive shape of the bonnet vents are entirely dictated by function. These direct the hot air exiting the front radiators, leaving a channel of clean, cold air to feed the roof-mounted engine intake snorkel. The hot air directed over the roof of the car helps to boost downforce, yet it is kept away from the car’s flanks, ensuring fresh air is ingested by the main side-mounted radiators.
At the rear, the LED taillights are invisible by day but offer attractive and ultra thin strips of light by night. They are as thin as possible to maximize the surface area for hot air to escape. This signature rear graphic, which highlights the very edge of the bodywork, was inspired by sports prototype racers, says Stephenson. The rear of the car is entirely open to aid cooling and to extract turbulent air from the rear wheel arches and help aerodynamic flow.
INSPIRED BY THE McLAREN F1 AND FORMULA 1
Stephenson said he was inspired by two cars from the brand’s history when he and his team designed the McLaren P1™: the iconic McLaren F1 road car of 1993, and Lewis Hamilton’s championship winning 2008 Formula 1 car, the MP4-23. He explains: ‘The 2008 season was the last year they allowed Formula 1 cars to have all the aero appendages. We had the MP4-23 in the studio for about a year, and we studied every element of the car, which was styled for function, not beauty. However, they still made the car look beautiful. The car’s scoops and slats influenced the style of the McLaren P1™. Every duct and every surface does a job, either in aero or cooling.’
The McLaren F1 road car was a vehicle Stephenson tried to ‘recall but not imitate. The greenhouse graphic on the side is similar, especially the rear three quarter window. The dihedral doors are similar, so is the low front cowl and the side swage lines. The roof snorkel is a feature carried over from the F1.’ The snorkel itself forms part of the carbon fibre MonoCage.
The dihedral doors of the McLaren P1™ are instrumental in the car’s astonishing aerodynamic performance. Unlike the 12C, they have two hinges not one. ‘Two small hinges are lighter,’ says Stephenson. ‘The door is also closer to the body when open.’ Their complex shape helps channel clean air to the side mounted radiators, and also cuts the turbulence normally experienced along the side of a car. Their scalloped shapes are all part of Stephenson’s philosophy to ‘push in’ surfaces, and create an almost ‘exoskeleton’ approach.
‘I wanted to take out as much visual weight as possible, to have a car that was really lean; a car with absolutely no fat between the mechanicals and the skin. It’s as though we stuck a tube inside and sucked all the air out, a dramatic honest shape but also a very beautiful one. It was all part of the engineering and design approach to fanatically take out weight.’
THE FINAL DESIGN
McLaren has been engaging with potential customers actively in the last few months to get their views on the McLaren P1™, about the car’s styling. Their unanimous verdict on the styling was not to change the car presented last September in Paris. So unusually, the McLaren P1™ has translated to production form with very little change. In fact just one, the addition of LTR ducts ahead of each of the front wheels to further aid cooling and optimise downforce.
McLaren has closely monitored demand so as to maintain exclusivity, and announced a production number of just 375 units.