Audi A8 S8 Second generation 

 The second-generation Audi A8 (Typ 4E) built on the Volkswagen Group D3 platform was introduced in November 2002 in Europeand in early 2003 in the United States. The model was longer than the previous generation, with room for four or five large adult occupants in the cabin, depending on rear seat configuration.

As with the previous version, two body variants of the second generation A8 are offered, the A8 (standard, or short wheelbase), and the long-wheelbase (LWB) A8 L. The A8 L adds 120 mm (4.7 inches) to the rear legroom and 11 mm (0.43 in) to the overall height of the car.

In 2005, new internal combustion engines became available. For European and Asian market customers, the entry-level 3.0-litre V6 engine was replaced with a new 3.2-litre unit featuring Fuel Stratified Injection (FSI), which it shared with the Audi B7 A4 and Audi C6 A6. The top-of-the-line W12 version debuted that year. The advantage of the W12 engine layout is its compact packaging, allowing Audi to build a 12-cylinder sedan with all-wheel drive, whereas a conventional V12 could only have a rear-wheel drive configuration as it would have no space in the engine bay for a differential and other components required to power the front wheels. In fact, Audi's 6.0-litre W12 is actually slightly smaller by overall dimensions than the 4.2-litre V8.

In addition to the added powertrains, Audi restyled the D3 platform A8 range slightly in 2005, giving all variants a taller, wider trapezoidal single-frame grille. The top-of-the-line W12 engined W12 version was the first model to be equipped with this grille; V8 engined models were fitted with the new grille the following year.

The D3 generation A8 introduced the 235 kW (315 hp) 4.2-litre Turbocharged Direct Injection (TDI) V8 engine (subsequently uprated to 240 kW (322 hp)). The engine uses two turbochargers and two intercoolers, with each turbocharger functioning exclusively for one bank of four cylinders.

From 2005 or 2006 Audi started offering the optional 1,000-watt 14-channel ICEpower Bang & Olufsen sound system.

From September 2007 for the 2008 model year, the A8 received a facelift and also received new electronic safety systems. "Audi Side Assist" detects cars in the A8's blind spots. "Audi Lane Assist" helps when the driver attempts to change lanes without signalling first.

A8 L W12 quattro Security

It is an armoured vehicle with B6+ and B7 (European standard) ballistic ratings. It includes a W12 engine rated 331 kW (450 PS) and 580 N·m (428 lbf·ft), emergency exit system featuring pyrotechnic blown-out doors, fire extinguisher system with spray jets located in the engine compartment, underbody and in the wheel arches; smoke extractor in passenger compartment, run flat tyres, LED flashers in the exterior mirrors. Buyers are also offered facility to dispatch two drivers on a special training course.

S8 5.2 FSI quattro

The S8 high-performance sports variant, now called the "Audi S8 5.2 FSI quattro" was announced in the last quarter of 2005 and full production started in June 2006 and ended in September 2009.

The S8 includes subtle detailing to distinguish it from its related A8. The trapezoidal "single-frame" grille bears the characteristic Audi "S model" vertical strut detail which are highlighted in a chrome finish. "S8" badging is displayed front and rear, whilst "V10" badges are displayed on each front wing above the side-repeater indicators. The rear boot-lid incorporates a subtle rear spoiler, and the rear is finished with four chromed oval exhaust tailpipes. Adaptive Xenon-plus high-intensity discharge (HID) headlamps include static turning lights, along with "swiveling" dynamic cornering lights. Daytime running lamps are five light-emitting diodes (LEDs) incorporated into a cloverleaf designed reflector, incorporated into the main headlamp housing.

The D3 series S8 features a 5.2-litre all-aluminium alloy four-valves per cylinder V10 petrol engine. This engine is a derivative of the Lamborghini Gallardo's original 5.0-litre Lamborghini V10,which was also developed under the Volkswagen Group ownership. On this Audi-only variant, compared to the Lamborghini engine, it features a longer stroke and wider bore—which increases the displacement of the engine, and produces more torque at lower revs, making it more suitable for the larger and heavier full-sized luxury Audi application. It produces 331 kW (444 hp) of power and 540 N·m (398 lb·ft) of torque. By having its bore whittled out an additional 2 millimetres (0.1 in), displacement in the S8 application increases from 5.0- to 5.2-litres. The engine also features Audi's direct-injection system, called Fuel Stratified Injection (FSI).

A sports-optimised ZF 6HP26-A61 six-speed tiptronic automatic transmission with "Dynamic Shift Programme" (DSP) and "sport" mode, with steering wheel mounted paddle-shifters, is the only offering. Output is transmitted via Audi's quattro all-wheel drive system, initially using the Torsen T-2 50:50 dynamic centre differential, and from 2007 for the 2008 model year, utilising the Torsen T-3 asymmetric dynamic centre differential, with a "default" torque distribution of 40 percent to the front axle and 60 percent to the rear.

The S8's top speed is electronically limited to 250 km/h (155 mph). Audi's factory performance claims indicate a 0 to 100 km/h (0 to 62 mph) time of 5.1 seconds whilst consuming 98 RON unleaded petrol. The S8 has similar performance to Audi's own top-of-the-line A8 L W12, though the W12 is more expensive, has more torque, and built on a longer wheelbase. Compared to the A8 L W12, the S8 has sportier mechanical features such as a firmer suspension, larger wheels, and ceramic brakes. The shorter wheelbase and 10-cylinder engine save weight for better handling, but at 5.4 seconds from 0-60 mph the S8 trails the W12. The S8's top speed is electronically limited to 250 kilometres per hour (155.3 mph).

The S8, like its related A8, utilises a multi-link suspension layout front and rear, with pressurised air springs. However, for the S8, the effective spring and damper rates are noticeably firmer, along with re-engineered suspension mounts.

The brake system consists of radially ventilated discs all round. The discs are clamped with gloss-black painted dual-piston calipers up front, and a single-piston sliding caliper at the rear, coupled to an electro-mechanical parking brake. A Bosch ESP 5.7 (later upgraded to ESP 8.0) electronic stability control, with ABS, brake assist, EBD complete the brake system. Optional "Audi ceramic" carbon fibre-reinforced silicon carbide (C/SiC) composite front and rear brakes are available, which use radially vented, and floating SGL Carbon discs, with anthracite grey painted twelve-piston fixed Brembo monobloc alloy calipers. Standard alloy wheels consist of 20-inch "S design" alloy wheels.