2005 Audi A4 vs. 2008 Audi A8
To start off, 2008 Audi A8 is newer by 3 year(s). Which means there will be less support and parts availability for 2005 Audi A4. In addition, the cost of maintenance, including insurance, on 2005 Audi A4 would be higher. At 4,172 cc (8 cylinders), 2008 Audi A8 is equipped with a bigger engine. In terms of performance, 2008 Audi A8 (330 HP @ 6500 RPM) has 160 more horse power than 2005 Audi A4. (170 HP @ 6300 RPM) In normal driving conditions, 2008 Audi A8 should accelerate faster than 2005 Audi A4. With that said, vehicle weight also plays an important factor in acceleration. 2008 Audi A8 weights approximately 385 kg more than 2005 Audi A4. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2008 Audi A8 is four wheel drive (4WD), it will have significant more traction and grip than 2005 Audi A4. In wet, icy, snow, or gravel driving conditions, 2008 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, 2008 Audi A8 (431 Nm @ 3500 RPM) has 206 more torque (in Nm) than 2005 Audi A4. (225 Nm @ 1750 RPM). This means 2008 Audi A8 will have an easier job in driving up hills or pulling heavy equipment than 2005 Audi A4.
Compare all specifications:
| 2005 Audi A4 | 2008 Audi A8 | |
| Make | Audi | Audi |
| Model | A4 | A8 |
| Year Released | 2005 | 2008 |
| Body Type | Sedan | Sedan |
| Engine Position | Front | Front |
| Engine Size | 1784 cc | 4172 cc |
| Engine Cylinders | 4 cylinders | 8 cylinders |
| Engine Type | in-line | V |
| Valves per Cylinder | 5 valves | 5 valves |
| Horse Power | 170 HP | 330 HP |
| Engine RPM | 6300 RPM | 6500 RPM |
| Torque | 225 Nm | 431 Nm |
| Torque RPM | 1750 RPM | 3500 RPM |
| Engine Bore Size | 81 mm | 84.5 mm |
| Engine Stroke Size | 86 mm | 93 mm |
| Drive Type | Front | 4WD |
| Transmission Type | Automatic | Automatic |
| Number of Seats | 5 seats | 5 seats |
| Number of Doors | 4 doors | 4 doors |
| Vehicle Weight | 1525 kg | 1910 kg |
| Vehicle Length | 4550 mm | 5190 mm |
| Vehicle Width | 1770 mm | 1900 mm |
| Vehicle Height | 1430 mm | 1460 mm |
| Wheelbase Size | 2660 mm | 3080 mm |
| Fuel Consumption Overall | 9.4 L/100km | 11.9 L/100km |
| Fuel Tank Capacity | 70 L | 90 L |
