Uus otsepritse V8 turbokone X6 BMW peal.
Displacing 4.4 liters, the new V8 engine with Twin Turbo technology and direct gasoline injection (High Precision Injection) develops maximum output of 400 hp throughout a broad range of engine speed from 5,500-6,400 rpm. Engine torque reaches its peak of 450 lb-ft throughout an unusually large speed range from 1,800-4,500 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. The cooling effect of direct fuel injection also ensures a compression ratio quite unusual on a turbocharged engine, 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 technology 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-aluminum V8 engine 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 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 engine 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 lag" typical of a turbocharged engine with conventional technology, that is the time until the turbocharger builds up its boost, is virtually eliminated through the combination of two small turbos and the direct injection calibration.
A further advantage is that the engine revs up smoothly, 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-aspirated engine while offering the advantage of much lower weight and reduced package size.
Not only are the dimensions and weight of the new V8 unusually modest, but the fuel consumption is also exceptionally low for an engine of this caliber. A significant factor contributing to the superior fuel economy is double-VANOS infinite camshaft management, a technology characteristic of BMW engines. Indeed, this technology is also one of the reasons why 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 2900 psi. 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.
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