A class of its own: The new eight-cylinder with Twin Turbo Technology.
Supremacy as the most important feature – this applies to BMW’s X Models and to BMW’s eight-cylinder power units. And now the BMW X6 is adding an incomparably dynamic variant to the line-up of BMW X Models, with the world’s first Sports Activity Coupé for the first time boasting a particularly sporting and dynamic eight-cylinder.
Displacing 4.4 litres, the new V8 power unit with Twin Turbo technology and direct gasoline injection (High Precision Injection) develops maximum output of 300 kW/407 hp throughout a broad range of engine speed from 5,500–6,400 rpm. Engine torque reaches its peak of 600 Newton-metres/442 lb-ft throughout an unusually large speed range from 1,750–4,500 rpm. The spontaneous, intense and long-lasting thrust generated in this way is the result of Twin Turbo technology already featured on BMW’s most powerful straight-six combined with High Precision Injection.
On the new V8 the cooling effect of direct fuel injection also ensures a compression ratio quite unusual on a turbocharged power unit, helping to give the engine an even higher level of all-round efficiency.
The position of the turbochargers and catalytic converters in the V-section between the two rows of cylinders is likewise an innovation in techno-logy allowing particularly compact engine dimensions and at the same time requiring new configuration of the intake and exhaust ducts. This means shorter intake and exhaust manifolds and larger cross-sections significantly reducing pressure losses on both the intake and exhaust side.
The all-aluminium V8 power unit developed for the BMW X6 offers all the qualities typical of an eight-cylinder in incomparably sporting style. In practice this means a combination of superior torque at low engine speeds with an ongoing surge of power and performance up to the higher speed range.
The BMW X6 xDrive50i accelerates from 0–100 km/h in just 5.4 seconds and boasts ample power reserves for fascinating acceleration also at higher speeds. Top speed is a truly impressive 250 km/h or 155 mph limited electronically by the engine control unit.
Twin Turbo technology featured for the first time on an eight-cylinder gasoline engine.
The power and performance characteristics of the new V8 result to a large extent from Twin Turbo technology, the use of two turbochargers for the first time on an eight-cylinder power unit serving to boost both engine output and torque with maximum efficiency. Each of the two turbochargers supplies compressed air to four cylinders at a time, ensuring particular spontaneity and a direct reaction to the gas pedal.
As with the straight-six featuring Twin Turbo technology, the “turbo gap” typical of a turbocharged engine with conventional technology, that is the time-lag until the turbocharger builds up its power and boost, is virtually eliminated by this superior technology.
A further advantage is that the engine revs up smoothly and full of power, maintaining its high torque consistently throughout an unusually broad range of engine speed. In its power and performance characteristics, therefore, the engine is comparable to a significantly larger normal-aspiration power unit while offering the advantage of much lower weight also thanks to its all-aluminium crankcase.
Not only the dimensions and weight of the new V8 are unusually modest, but also the fuel consumption exceptionally low for an engine of this calibre.
A significant factor contributing to the superior fuel economy is double- VANOS infinite camshaft management, a technology characteristic of BMW power units. Indeed, this technology is also one of the reasons while the V8 – over and above its superior fuel economy – develops exceptionally high torque from low engine speeds.
High Precision Injection also plays a key role in the efficient use of fuel. This second generation of direct gasoline injection uses piezo-injectors positioned directly next to the spark plugs in the cylinder head and delivering fuel into the combustion chambers at a pressure of 200 bar. The advantage is extremely precise dosage of fuel, with the further benefit of reduced emissions and improved engine acoustics. And last but not least, it almost goes without saying that the engine fulfils both the US ULEV II emissions standard as well as the EU5 requirements in Europe.
The new V8 power unit ist the most efficient engine in its class. Combined with a number of further technologies developed in the overall context of BMW EfficientDynamics, the engine gives the BMW X6 xDrive50i fuel consumption and emission figures significantly better than other eight-cylinder vehicles competing with the BMW X Models. Average fuel consumption of the BMW X6 xDrive50i is 12.5 litres/100 km (equal to 22.6 mpg imp), the CO2 rating is 299 grams per kilometre.