2008 Audi S6 vs. 2006 BMW 645
To start off, 2008 Audi S6 is newer by 2 year(s). Which means there will be less support and parts availability for 2006 BMW 645. In addition, the cost of maintenance, including insurance, on 2006 BMW 645 would be higher. At 5,202 cc (10 cylinders), 2008 Audi S6 is equipped with a bigger engine. In terms of performance, 2008 Audi S6 (429 HP @ 6800 RPM) has 101 more horse power than 2006 BMW 645. (328 HP @ 6100 RPM). In normal driving conditions, 2008 Audi S6 should accelerate faster than 2006 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 2008 Audi S6 weights approximately 100 kg more than 2006 BMW 645. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2008 Audi S6 is four wheel drive (4WD), it will have significant more traction and grip than 2006 BMW 645. In wet, icy, snow, or gravel driving conditions, 2008 Audi S6 will offer significantly more control. With that said, do keep in mind that many other factors such as speed and the wear on your tires can also have significant impact on traction and control. Let's talk about torque, 2008 Audi S6 (540 Nm @ 3000 RPM) has 90 more torque (in Nm) than 2006 BMW 645. (450 Nm @ 3600 RPM). This means 2008 Audi S6 will have an easier job in driving up hills or pulling heavy equipment than 2006 BMW 645.
Compare all specifications:
| 2008 Audi S6 | 2006 BMW 645 | |
| Make | Audi | BMW |
| Model | S6 | 645 |
| Year Released | 2008 | 2006 |
| Body Type | Sedan | Coupe |
| Engine Position | Front | Front |
| Engine Size | 5202 cc | 4398 cc |
| Engine Cylinders | 10 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 429 HP | 328 HP |
| Engine RPM | 6800 RPM | 6100 RPM |
| Torque | 540 Nm | 450 Nm |
| Torque RPM | 3000 RPM | 3600 RPM |
| Engine Compression Ratio | 12.5:1 | 10.0:1 |
| Fuel Type | Gasoline | Gasoline |
| Top Speed | 250 km/hour | 250 km/hour |
| Acceleration 0-100mph | 5.2 seconds | 5.6 seconds |
| Drive Type | 4WD | Rear |
| Transmission Type | Automatic | Automatic |
| Number of Seats | 5 seats | 4 seats |
| Number of Doors | 4 doors | 2 doors |
| Vehicle Weight | 1910 kg | 1810 kg |
| Vehicle Length | 4920 mm | 4830 mm |
| Vehicle Width | 1870 mm | 1860 mm |
| Vehicle Height | 1460 mm | 1380 mm |
| Wheelbase Size | 2850 mm | 2790 mm |
| Fuel Consumption Overall | 13.4 L/100km | 13.3 L/100km |
| Fuel Tank Capacity | 80 L | 70 L |
