2003 Audi A8 vs. 2006 BMW 645
To start off, 2006 BMW 645 is newer by 3 year(s). Which means there will be less support and parts availability for 2003 Audi A8. In addition, the cost of maintenance, including insurance, on 2003 Audi A8 would be higher. At 4,398 cc (8 cylinders), 2006 BMW 645 is equipped with a bigger engine. In terms of performance, 2006 BMW 645 (328 HP @ 6100 RPM) has 56 more horse power than 2003 Audi A8. (272 HP @ 3750 RPM) In normal driving conditions, 2006 BMW 645 should accelerate faster than 2003 Audi A8. With that said, vehicle weight also plays an important factor in acceleration. 2003 Audi A8 weights approximately 10 kg more than 2006 BMW 645.
Because 2003 Audi A8 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, 2003 Audi A8 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, 2003 Audi A8 (650 Nm @ 1800 RPM) has 200 more torque (in Nm) than 2006 BMW 645. (450 Nm @ 3600 RPM). This means 2003 Audi A8 will have an easier job in driving up hills or pulling heavy equipment than 2006 BMW 645.
Compare all specifications:
| 2003 Audi A8 | 2006 BMW 645 | |
| Make | Audi | BMW |
| Model | A8 | 645 |
| Year Released | 2003 | 2006 |
| Body Type | Sedan | Coupe |
| Engine Position | Front | Front |
| Engine Size | 3936 cc | 4398 cc |
| Engine Cylinders | 8 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 272 HP | 328 HP |
| Engine RPM | 3750 RPM | 6100 RPM |
| Torque | 650 Nm | 450 Nm |
| Torque RPM | 1800 RPM | 3600 RPM |
| Engine Compression Ratio | 17.5:1 | 10.0:1 |
| Fuel Type | Diesel | Gasoline |
| Top Speed | 250 km/hour | 250 km/hour |
| Acceleration 0-100mph | 6.8 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 | 1820 kg | 1810 kg |
| Vehicle Length | 5190 mm | 4830 mm |
| Vehicle Width | 1900 mm | 1860 mm |
| Vehicle Height | 1460 mm | 1380 mm |
| Wheelbase Size | 3080 mm | 2790 mm |
| Fuel Consumption Overall | 9.6 L/100km | 13.3 L/100km |
| Fuel Tank Capacity | 90 L | 70 L |
