2008 Audi S8 vs. 2005 BMW 645
To start off, 2008 Audi S8 is newer by 3 year(s). Which means there will be less support and parts availability for 2005 BMW 645. In addition, the cost of maintenance, including insurance, on 2005 BMW 645 would be higher. At 5,204 cc (10 cylinders), 2008 Audi S8 is equipped with a bigger engine. In terms of performance, 2008 Audi S8 (450 HP @ 7000 RPM) has 112 more horse power than 2005 BMW 645. (338 HP @ 6100 RPM). In normal driving conditions, 2008 Audi S8 should accelerate faster than 2005 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 2005 BMW 645 weights approximately 555 kg more than 2008 Audi S8.
Because 2008 Audi S8 is all wheel drive (AWD), it will have significant more traction and grip than 2005 BMW 645. In wet, icy, snow, or gravel driving conditions, 2008 Audi S8 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 S8 (540 Nm @ 3500 RPM) has 101 more torque (in Nm) than 2005 BMW 645. (439 Nm @ 3600 RPM). This means 2008 Audi S8 will have an easier job in driving up hills or pulling heavy equipment than 2005 BMW 645.
Compare all specifications:
| 2008 Audi S8 | 2005 BMW 645 | |
| Make | Audi | BMW |
| Model | S8 | 645 |
| Year Released | 2008 | 2005 |
| Body Type | Sedan | Coupe |
| Engine Position | Front | Front |
| Engine Size | 5204 cc | 4390 cc |
| Engine Cylinders | 10 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 450 HP | 338 HP |
| Engine RPM | 7000 RPM | 6100 RPM |
| Torque | 540 Nm | 439 Nm |
| Torque RPM | 3500 RPM | 3600 RPM |
| Fuel Type | Gasoline - Premium | Gasoline - Premium |
| Top Speed | 244 km/hour | 250 km/hour |
| Drive Type | AWD | Rear |
| Transmission Type | Automatic | Automatic |
| Number of Seats | 5 seats | 4 seats |
| Number of Doors | 4 doors | 2 doors |
| Vehicle Weight | 1160 kg | 1715 kg |
| Vehicle Length | 5070 mm | 4830 mm |
| Vehicle Width | 1900 mm | 1860 mm |
| Vehicle Height | 1430 mm | 1380 mm |
| Wheelbase Size | 2950 mm | 2790 mm |
| Fuel Consumption Highway | 12.4 L/100km | 9.4 L/100km |
| Fuel Consumption Overall | 15.7 L/100km | 11.8 L/100km |
| Fuel Tank Capacity | 90 L | 70 L |
