17 de maio de 2013

Slowly Porsche reveals more about the 918 Spyder


Over the last year, Porsche had no problem showing the world its new super-car, the 918 Spider. They even tested the car on the North Loop of the Nürburgring track in front of many international journalists, and the fact that it has a hybrid powertrain is not new for a long time.

Starting with the chassis, the 918 Spyder uses a a type of monocoque entirely made out of carbon fibre reinforced polymer (CFRP), with several additional crash elements at the front and rear to absorb and reduce the energy of a collision. The car has an unladen weight (no passenger, fluids or battery) of approximately 1640kg (3616lbs), which is not so little.

All the mechanical parts were installed as low as possible, meaning that the car has a low center of gravity, which in this case is slightly above the wheel hubs. It also has a 43/57 (front/rear) weight distribution, which is decent for a four-wheel drive car with rear-axle steering (similar to the 911 Turbo). All of this, together with a 4643mm length, a 1940mm width, a height of 1167mm and a wheelbase with 2730mm, this will be a very stable car.

This hybrid powertrain consists of a 4.6 liter V8 engine, which alone produces 608PS (447kW or 599hp) and 530Nm (391lb/ft) of torque, a hybrid module connected to the petrol engine with a 156PS (115kW or 154hp) electric motor and a decoupler, and an independent electric motor with 129PS (95kW or 127hp) driving the front wheels.

In total, this Porsche has close to 890PS (655kW or 878hp) and over 800Nm (590lb/ft), reaching 1275Nm (940lb/ft) of maximum torque (crankshaft equivalent combined, 7th gear). Connected to the hybrid module and the combustion engine is the seven-speed automatic transmission (PDK) that drives the rear wheels. The electric motor mounted on the front also has a gearbox which is disconnected when the car reaches 235km/h (146mph).

Powering the electric motors is a liquid-cooled lithium-ion battery comprising 312 individual cells with a 6.8kWh capacity. When driving only in electric mode, the 918 Spyder, has a range of approximately 30km (18 miles) and a top speed of 150km/h (93mph). With the help of the petrol engine, it can reach a top speed of more than 340km/h (211mph) and accelerate from standstill to 100km/h (62mph) in 2.8 seconds, to 200km/h (124mph) in 7.9 seconds and up to 300km/h (186mph) in 23 seconds, while having a combined fuel consumption (NEDC) of 3.3l/100km (85.6 UK mpg or 71.3 USA mpg) and CO2 emissions of just 79g/km.

Source: Porsche