A8 new Long & A8 new Long W12

Машина длинее базы на 130 милиметров

Новый W12 FSI мотор теперь объемом 6.3 литра 500л/с и 625н*м крутящего.

С этим моторм Audi A8 разгоняется 0-100 за 4.9 с традиционным ограном в 250км/ч.

Обещанный средний расход 12л на 100 км.

 

пока все что есть и походу расточенный

The Audi A8 L W12 quattro: Splendor and efficiency
Twelve cylinders are the ultimate engine configuration, a tradition that still applies in the large luxury car class. The first-generation A8 was available with an engine of this type from 2001 on, and a developed version could be obtained from 2004 on in the following model. Audi’s engineers have now thoroughly revised the W12. Its displacement has been increased, and gasoline direct injection boosts its output and its efficiency.

The 6.3 FSI engine has an output of 368 kW (500 hp) and delivers its peak torque of 625 Nm (460.98 lb-ft) at engine speeds at 3,250 rpm. It gives the long-wheelbase Audi A8 the kind of performance normally expected of a sports car: it sprints from 0 to 100 km/h (62.14 mph) in only 4.9 seconds and effortlessly reaches its governed top speed of 250 km/h (155.34 mph).

A fascinating flow of power is available in every situation, but the fuel consumption too sets new standards: the EU cycle test result is only 12.0 liters per 100 kilometers (19.6 US mpg), a figure well below that of competitors’ cars with V12 engines. The previous 6.0-liter engine, which had a power output of 331 kW (450 hp), recorded a fuel consumption of 13.6 l/100 km (17.3 US mpg) – the difference of 1.6 l/100 km is equivalent to a 12 percent improvement.

The engine is known as the W12 because of its unusual layout: it has four rows of three cylinders with a 15-degree included angle between the two offset rows of cylinders in each broad cylinder block. The V angle between the two blocks is 72 degrees. This layout makes the W12 engine exceptionally compact: only just over 50 centimeters (19.69 in) long and therefore distinctly shorter than a V8. Height and width are both in the region of 70 centimeters (27.56 in).

The W12, in its latest form with a displacement of 6,299 cc, is an undersquare design. Its bore and stroke are 86.0 and 90.4 millimeters (3.39 x 3.56 in) respectively. Compared with the previous version the engineers have enlarged the cylinder bore. The forged crankshaft has a 12-degree angle of crankpin offset, so that the mixture in the 12 cylinders is ignited at the ideal interval of 60 degrees. The engine therefore runs exceptionally smoothly, and the car’s occupants are unlikely to sense any of this supreme power at work unless it is at high engine speeds and severe loads.

The W12 engine weighs only 247 kilograms (545 lb), an impressive value to which the crankcase makes a major contribution. This is a lightweight, high-strength aluminum-silicon alloy casting with a gray cast iron lower cross-member into which the bearing pedestals are embedded. The pistons are forged from a high-strength light alloy and have angled crowns because of their V position in the cylinder blocks.

Each of the W12 engine’s aluminum cylinder heads contains two camshafts; these can be repositioned hydraulically by an amount equivalent to 52 degrees of crankshaft rotation. Altogether, the four camshafts operate 48 valves by way of low-friction roller cam followers, and are themselves driven by chains from an intermediate shaft.

For use in the long-wheelbase A8, Audi’s engineers have converted the W12 engine to FSI gasoline direct injection. This involved considerable modifications to the cylinder heads. Fuel is injected into the combustion chambers at a pressure of up to 130 bar. A high 11.8:1 compression ratio boosts power output and efficiency. The inlet ports are specially shaped to impart swirl to the incoming airflow and make combustion more efficient.

The W12 engine’s low fuel consumption compared with its competitors is to a large extent due to Audi’s modular efficiency platform. These are used in the entire A8 model line. The crankshaft and timing chains have been intensively optimized to reduce friction, and a recuperation system recovers energy that would otherwise be wasted when the car is braked. The innovative thermal management system shuts down the coolant circuit for a time after the cold engine has been started. This warms up the engine oil more rapidly and shortens the operating period in which friction is still high.