Porsche's Most Advanced Car
The 918's main source of power is a race-inspired 4.6-liter V8 engine that churns out 608 horsepower at 8,600 rpms and 390 lb-ft. of torque at 6,600 rpms. Interestingly, it does not power any auxiliary accessories such as the alternator or the air conditioning compressor, meaning that it is neatly installed in the engine bay without any belts or pulleys. The aforementioned top pipes replace the traditional exhaust pipes and help route heat away from the lithium-ion battery pack as quickly and efficiently as possible.
The V8 sends power to the rear wheels via a seven-speed PDK dual-clutch transmission mounted upside down to achieve a lower center of gravity.
A 154-horsepower hybrid module installed on the rear axle and a 127-horsepower electric motor located on the front axle are both powered by the aforementioned lithium-ion battery pack. Liquid-cooled, the pack can be fully charged in four hours when plugged into a 230-volt German-spec household outlet, or in 25 minutes using Porsche's Speed Charging Station.
Combined, the three power sources churn out 887 horsepower and over 590 lb-ft. of torque, enabling the 918 to sprint from zero to 62 mph in 2.8 seconds and from zero to 124 mph in 7.9 seconds. Top speed is rated at over 211 mph. Alternatively, when driven conservatively the 918 can return up to 91 mpg in a mixed European cycle while emitting around 79 grams of CO2 per kilometer, making the super car cleaner than most economy sub-compacts.
The drivetrain operates in one of five modes that can be activated with a knob on the steering wheel. The default mode is E-Power, which gives the car an electric range of 18 miles at speeds of up to 93 mph. In Hybrid Mode, all three power sources work together to return the best possible fuel economy. Sport Hybrid runs the V8 engine continuously while regularly using the electric motors to provide boost. Race Hybrid changes the gear ratios and runs the electric motors at their maximum power for a short time. The last mode is Hot Lap, which uses all of the available battery power to delivery the drivetrain's full potential.
The 918 packs a four-wheel steering system that turns the rear wheels in the opposite direction as the front wheels at low speeds, and in the same direction at high speeds. Porsche explains the four-wheel steering equates to adding 50 horsepower or removing 220 pounds from the car when it is driven on a track.
The car is also equipped with Porsche's Active Aerodynamic system, a feature that adjusts add-ons such as the rear wing based on driving conditions. It has three modes: Sport, E-Power and Race.
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