A lightweight carbon-fiber structure, high-power hybrid driveline, active ride height, and racing aerodynamics systems all help to make the McLaren P1 a technical tour de force. Although it was unveiled at the Paris Show last September, we have had to wait until the 2013 Geneva Motor Show for the full story.
Since the car is not bound by the racing rulebook, McLaren has included adjustable suspension and active aerodynamics in the P1’s extensive equipment list. An active rear wing and underbody devices help to optimize the airflow. The active wing can be extended from the bodywork by 120 mm (4.7 in) for road use and up to 300 mm (11.8 in) for racing. A DRS (drag reduction system) can alter the rear wing angle to reduce drag by 23%, controlled by the driver.
McLaren calls the adjustable ride height suspension RaceActive Chassis Control (RCC). The system, working with the hydropneumatic suspension, can lower the ride height by 50 mm (2.0 in) in Race mode to improve ground-effect aerodynamics. Add in adaptive spring rates, roll control, pitch control, and damping for a wide range of adjustment to suit the car on both road and track. McLaren claims that the P1 can corner with forces exceeding 2 g in Race mode, when the spring rates stiffen by 300%.
Like the McLaren F1 of 1993, the P1 is built from carbon fiber. Both the MonoCage chassis and aerodynamic body panels are made from the material, and the chassis incorporates Kevlar too. Carbon fiber is also used for the dashboard, floor, headlining, doors, and sills. The body is made from five main panels: the front clamshell, hood, rear clamshell, and the doors.
In Race mode, the car measures 1138 mm (44.8 in) tall. McLaren claims a smaller frontal area than any other production sports car and a Cd figure of 0.34. The only changes made to the design since the 2012 Paris Motor Show have been the addition of LTR ducts ahead of both front wheels to improve cooling and optimize downforce. McLaren quotes 600 kg (1320 lb) of downforce at 161 mph (259 km/h).
Considering that the car can call on a total of 903 bhp (673 kW) with 900 N·m (664 lb·ft), that downforce is a necessary part of the handling equation. The mid-mounted twin turbocharged 3.8-L V8 gasoline engine was jointly developed with Ricardo. It is a revised version of McLaren’s M838T engine, designed to optimize cooling and durability and accommodate the hybrid drive electric motor. It produces 727 bhp (542 kW) at 7500 rpm and 720 N·m (531 lb·ft) from 4000 rpm. Electric motor output is rated at 176 bhp (131 kW) and 130 N·m (96 lb·ft), although with a geared output, McLaren says this is effectively doubled. McLaren quotes CO2 emissions of under 200 g/km on the EU NEDC combined test.
Drive from both engine and motor is fed through the dual-clutch seven-speed automated transmission. The electric motor is used to apply negative torque at the gearshift point to ensure that engine speed falls faster, speeding the gearshift. The parallel hybrid drivetrain provides for an E-mode using electric power only for over 10 km (6 mi) at speeds up to 100 mph (160 km/h).
The lightweight batteries are mounted in the underbody of the MonoCage chassis, sealing the 96-kg (212-lb) unit inside the vehicle. McLaren claims a higher power density for the batteries than any other automotive battery pack on sale today. Coolant flow has been designed to ensure that each cell is cooled to the same temperature across the battery pack. A plug-in charger for the batteries, in addition to regenerative charging, provides a full recharge in 2 h or a 10-min 100% quick charge facility.
Power from the electric motor can be added at the touch of a button. McLaren quotes a 0-186 mph (0-300 km/h) time of less than 17 s, with an electronically limited top speed of 218 mph (350 km/h). The 0-62 mph (0-100 km/h) sprint is said to take less than 3 s.
Braking uses more F1 derived technology, with the system designed by Akebono using layered carbon ceramic brakes.