2004 Audi A8 vs. 2006 BMW Z4
To start off, 2006 BMW Z4 is newer by 2 year(s). Which means there will be less support and parts availability for 2004 Audi A8. In addition, the cost of maintenance, including insurance, on 2004 Audi A8 would be higher. At 5,998 cc, 2004 Audi A8 is equipped with a bigger engine. In terms of performance, 2004 Audi A8 (450 HP @ 6300 RPM) has 302 more horse power than 2006 BMW Z4. (148 HP @ 6200 RPM). In normal driving conditions, 2004 Audi A8 should accelerate faster than 2006 BMW Z4. With that said, vehicle weight also plays an important factor in acceleration. 2004 Audi A8 weights approximately 669 kg more than 2006 BMW Z4. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2004 Audi A8 is four wheel drive (4WD), it will have significant more traction and grip than 2006 BMW Z4. In wet, icy, snow, or gravel driving conditions, 2004 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, 2004 Audi A8 (560 Nm @ 4000 RPM) has 360 more torque (in Nm) than 2006 BMW Z4. (200 Nm @ 3600 RPM). This means 2004 Audi A8 will have an easier job in driving up hills or pulling heavy equipment than 2006 BMW Z4. 2004 Audi A8 has automatic transmission and 2006 BMW Z4 has manual transmission. 2006 BMW Z4 will offer better control over acceleration and deceleration in addition to better fuel efficiency overall. 2004 Audi A8 will be easier to drive especially in heavy traffic.
Compare all specifications:
| 2004 Audi A8 | 2006 BMW Z4 | |
| Make | Audi | BMW |
| Model | A8 | Z4 |
| Year Released | 2004 | 2006 |
| Body Type | Sedan | Convertible |
| Engine Position | Front | Front |
| Engine Size | 5998 cc | 1995 cc |
| Engine Type | W | in-line |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 450 HP | 148 HP |
| Engine RPM | 6300 RPM | 6200 RPM |
| Torque | 560 Nm | 200 Nm |
| Torque RPM | 4000 RPM | 3600 RPM |
| Engine Bore Size | 84.1 mm | 84 mm |
| Engine Stroke Size | 90.2 mm | 90 mm |
| Engine Compression Ratio | 11.0:1 | 10.5:1 |
| Fuel Type | Gasoline | Gasoline - Premium |
| Drive Type | 4WD | Rear |
| Transmission Type | Automatic | Manual |
| Number of Seats | 5 seats | 2 seats |
| Number of Doors | 4 doors | 2 doors |
| Vehicle Weight | 1995 kg | 1326 kg |
| Vehicle Length | 5060 mm | 4100 mm |
| Vehicle Width | 1900 mm | 1790 mm |
| Vehicle Height | 1450 mm | 1310 mm |
| Wheelbase Size | 2950 mm | 2500 mm |
