2006 BMW 645 vs. 2013 BMW M5
To start off, 2013 BMW M5 is newer by 7 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, 2013 BMW M5 (493 HP @ 7750 RPM) has 165 more horse power than 2006 BMW 645. (328 HP @ 6100 RPM) In normal driving conditions, 2013 BMW M5 should accelerate faster than 2006 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 2006 BMW 645 weights approximately 16 kg more than 2013 BMW M5.
Both vehicles are rear wheel drive (RWD) - it offers better handling in dry conditions; in addition, if you are looking to drift, both vehicles do the job better than front wheel drive vehicles. 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, 2013 BMW M5 (519 Nm @ 6100 RPM) has 69 more torque (in Nm) than 2006 BMW 645. (450 Nm @ 3600 RPM). This means 2013 BMW M5 will have an easier job in driving up hills or pulling heavy equipment than 2006 BMW 645.
Compare all specifications:
| 2006 BMW 645 | 2013 BMW M5 | |
| Make | BMW | BMW |
| Model | 645 | M5 |
| Year Released | 2006 | 2013 |
| Body Type | Convertible | Sedan |
| Engine Position | Front | Front |
| Engine Size | 4398 cc | 4395 cc |
| Engine Cylinders | 8 cylinders | 10 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 2 valves | 4 valves |
| Horse Power | 328 HP | 493 HP |
| Engine RPM | 6100 RPM | 7750 RPM |
| Torque | 450 Nm | 519 Nm |
| Torque RPM | 3600 RPM | 6100 RPM |
| Engine Bore Size | 92 mm | 92 mm |
| Engine Stroke Size | 83 mm | 75 mm |
| Engine Compression Ratio | 10.0:1 | 10.0 :1 |
| Fuel Type | Gasoline | Gasoline |
| Drive Type | Rear | Rear |
| Transmission Type | Manual | 6-speed manual |
| Number of Seats | 4 seats | 5 seats |
| Number of Doors | 2 doors | 4 doors |
| Vehicle Weight | 1836 kg | 1820 kg |
| Vehicle Length | 4830 mm | 4863 mm |
| Vehicle Width | 1860 mm | 1846 mm |
| Vehicle Height | 1380 mm | 1469 mm |
| Wheelbase Size | 2790 mm | 2889 mm |
| Fuel Tank Capacity | 70 L | 70 L |
