2002 Audi S4 vs. 2007 BMW 645
To start off, 2007 BMW 645 is newer by 5 year(s). Which means there will be less support and parts availability for 2002 Audi S4. In addition, the cost of maintenance, including insurance, on 2002 Audi S4 would be higher. At 4,398 cc (8 cylinders), 2007 BMW 645 is equipped with a bigger engine. In terms of performance, 2002 Audi S4 (339 HP @ 7000 RPM) has 11 more horse power than 2007 BMW 645. (328 HP @ 6100 RPM). In normal driving conditions, 2002 Audi S4 should accelerate faster than 2007 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 2002 Audi S4 weights approximately 30 kg more than 2007 BMW 645. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2002 Audi S4 is four wheel drive (4WD), it will have significant more traction and grip than 2007 BMW 645. In wet, icy, snow, or gravel driving conditions, 2002 Audi S4 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, 2007 BMW 645 (450 Nm @ 3600 RPM) has 40 more torque (in Nm) than 2002 Audi S4. (410 Nm @ 3500 RPM). This means 2007 BMW 645 will have an easier job in driving up hills or pulling heavy equipment than 2002 Audi S4.
Compare all specifications:
| 2002 Audi S4 | 2007 BMW 645 | |
| Make | Audi | BMW |
| Model | S4 | 645 |
| Year Released | 2002 | 2007 |
| Body Type | Station Wagon | Coupe |
| Engine Position | Front | Front |
| Engine Size | 4163 cc | 4398 cc |
| Engine Cylinders | 8 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 5 valves | 4 valves |
| Horse Power | 339 HP | 328 HP |
| Engine RPM | 7000 RPM | 6100 RPM |
| Torque | 410 Nm | 450 Nm |
| Torque RPM | 3500 RPM | 3600 RPM |
| Engine Compression Ratio | 11.0:1 | 10.0:1 |
| Drive Type | 4WD | Rear |
| Transmission Type | Manual | Manual |
| Number of Seats | 5 seats | 4 seats |
| Number of Doors | 5 doors | 2 doors |
| Vehicle Weight | 1720 kg | 1690 kg |
| Vehicle Length | 4580 mm | 4830 mm |
| Vehicle Width | 1790 mm | 1860 mm |
| Vehicle Height | 1450 mm | 1380 mm |
| Wheelbase Size | 2660 mm | 2790 mm |
| Fuel Tank Capacity | 66 L | 70 L |
