2003 Audi RS4 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 RS4. In addition, the cost of maintenance, including insurance, on 2003 Audi RS4 would be higher. At 4,398 cc (8 cylinders), 2006 BMW 645 is equipped with a bigger engine. In terms of performance, 2003 Audi RS4 (377 HP @ 6300 RPM) has 49 more horse power than 2006 BMW 645. (328 HP @ 6100 RPM). In normal driving conditions, 2003 Audi RS4 should accelerate faster than 2006 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 2006 BMW 645 weights approximately 107 kg more than 2003 Audi RS4.
Because 2003 Audi RS4 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 RS4 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, 2006 BMW 645 (450 Nm @ 3600 RPM) has 1 more torque (in Nm) than 2003 Audi RS4. (449 Nm @ 2500 RPM). This means 2006 BMW 645 will have an easier job in driving up hills or pulling heavy equipment than 2003 Audi RS4.
Compare all specifications:
| 2003 Audi RS4 | 2006 BMW 645 | |
| Make | Audi | BMW |
| Model | RS4 | 645 |
| Year Released | 2003 | 2006 |
| Body Type | Sedan | Coupe |
| Engine Position | Front | Front |
| Engine Size | 2671 cc | 4398 cc |
| Engine Cylinders | 6 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 5 valves | 4 valves |
| Horse Power | 377 HP | 328 HP |
| Engine RPM | 6300 RPM | 6100 RPM |
| Torque | 449 Nm | 450 Nm |
| Torque RPM | 2500 RPM | 3600 RPM |
| Fuel Type | Gasoline | Gasoline - Premium |
| Drive Type | 4WD | Rear |
| Transmission Type | Manual | Manual |
| Number of Seats | 5 seats | 4 seats |
| Number of Doors | 4 doors | 2 doors |
| Vehicle Weight | 1585 kg | 1692 kg |
| Vehicle Length | 4480 mm | 4830 mm |
| Vehicle Width | 1740 mm | 1860 mm |
| Vehicle Height | 1450 mm | 1380 mm |
| Wheelbase Size | 2610 mm | 2790 mm |
| Fuel Tank Capacity | 55 L | 70 L |
