2009 Audi A3 vs. 2006 BMW 645
To start off, 2009 Audi A3 is newer by 3 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 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 77 more horse power than 2009 Audi A3. (251 HP @ 6300 RPM) In normal driving conditions, 2006 BMW 645 should accelerate faster than 2009 Audi A3. With that said, vehicle weight also plays an important factor in acceleration. 2006 BMW 645 weights approximately 237 kg more than 2009 Audi A3. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2009 Audi A3 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, 2009 Audi A3 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 130 more torque (in Nm) than 2009 Audi A3. (320 Nm @ 3200 RPM). This means 2006 BMW 645 will have an easier job in driving up hills or pulling heavy equipment than 2009 Audi A3.
Compare all specifications:
| 2009 Audi A3 | 2006 BMW 645 | |
| Make | Audi | BMW |
| Model | A3 | 645 |
| Year Released | 2009 | 2006 |
| Body Type | Hatchback | Coupe |
| Engine Position | Front | Front |
| Engine Size | 3196 cc | 4398 cc |
| Engine Cylinders | 6 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 251 HP | 328 HP |
| Engine RPM | 6300 RPM | 6100 RPM |
| Torque | 320 Nm | 450 Nm |
| Torque RPM | 3200 RPM | 3600 RPM |
| Engine Bore Size | 84 mm | 92 mm |
| Engine Stroke Size | 95.9 mm | 82.7 mm |
| Engine Compression Ratio | 11.3:1 | 10.0:1 |
| Fuel Type | Gasoline | Gasoline - Premium |
| Drive Type | 4WD | Rear |
| Transmission Type | Automatic | Automatic |
| Number of Seats | 5 seats | 4 seats |
| Number of Doors | 3 doors | 2 doors |
| Vehicle Weight | 1455 kg | 1692 kg |
| Vehicle Length | 4290 mm | 4830 mm |
| Vehicle Width | 1970 mm | 1860 mm |
| Vehicle Height | 1430 mm | 1380 mm |
| Wheelbase Size | 2580 mm | 2790 mm |
| Fuel Consumption Overall | 9.8 L/100km | 11.8 L/100km |
| Fuel Tank Capacity | 55 L | 70 L |
