2009 Audi A4 vs. 2005 Audi A8
To start off, 2009 Audi A4 is newer by 4 year(s). Which means there will be less support and parts availability for 2005 Audi A8. In addition, the cost of maintenance, including insurance, on 2005 Audi A8 would be higher. At 4,178 cc (8 cylinders), 2005 Audi A8 is equipped with a bigger engine. In terms of performance, 2005 Audi A8 (335 HP @ 4000 RPM) has 177 more horse power than 2009 Audi A4. (158 HP @ 4500 RPM) In normal driving conditions, 2005 Audi A8 should accelerate faster than 2009 Audi A4. With that said, vehicle weight also plays an important factor in acceleration. 2005 Audi A8 weights approximately 1015 kg more than 2009 Audi A4. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Let's talk about torque, 2005 Audi A8 (430 Nm) has 180 more torque (in Nm) than 2009 Audi A4. (250 Nm). This means 2005 Audi A8 will have an easier job in driving up hills or pulling heavy equipment than 2009 Audi A4.
Compare all specifications:
| 2009 Audi A4 | 2005 Audi A8 | |
| Make | Audi | Audi |
| Model | A4 | A8 |
| Year Released | 2009 | 2005 |
| Body Type | Sedan | Sedan |
| Engine Position | Front | Front |
| Engine Size | 1798 cc | 4178 cc |
| Engine Cylinders | 4 cylinders | 8 cylinders |
| Engine Type | in-line | V |
| Valves per Cylinder | 4 valves | 5 valves |
| Horse Power | 158 HP | 335 HP |
| Engine RPM | 4500 RPM | 4000 RPM |
| Torque | 250 Nm | 430 Nm |
| Engine Bore Size | 82.5 mm | 85 mm |
| Engine Stroke Size | 84.1 mm | 93 mm |
| Engine Compression Ratio | 9.6:1 | 11.0:1 |
| Number of Seats | 5 seats | 5 seats |
| Number of Doors | 4 doors | 4 doors |
| Vehicle Weight | 930 kg | 1945 kg |
| Vehicle Length | 4710 mm | 5060 mm |
| Vehicle Width | 2010 mm | 1900 mm |
| Vehicle Height | 1430 mm | 1450 mm |
| Wheelbase Size | 2810 mm | 2950 mm |
| Fuel Consumption Overall | 7.4 L/100km | 11.8 L/100km |
| Fuel Tank Capacity | 65 L | 90 L |
