2003 BMW 645 vs. 2008 Mercedes-Benz R
To start off, 2008 Mercedes-Benz R is newer by 5 year(s). Which means there will be less support and parts availability for 2003 BMW 645. In addition, the cost of maintenance, including insurance, on 2003 BMW 645 would be higher. At 6,208 cc (8 cylinders), 2008 Mercedes-Benz R is equipped with a bigger engine. In terms of performance, 2008 Mercedes-Benz R (503 HP @ 6800 RPM) has 182 more horse power than 2003 BMW 645. (321 HP @ 6100 RPM) In normal driving conditions, 2008 Mercedes-Benz R should accelerate faster than 2003 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 2008 Mercedes-Benz R weights approximately 480 kg more than 2003 BMW 645. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2008 Mercedes-Benz R is four wheel drive (4WD), it will have significant more traction and grip than 2003 BMW 645. In wet, icy, snow, or gravel driving conditions, 2008 Mercedes-Benz R 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 Mercedes-Benz R (630 Nm @ 5200 RPM) has 180 more torque (in Nm) than 2003 BMW 645. (450 Nm @ 3600 RPM). This means 2008 Mercedes-Benz R will have an easier job in driving up hills or pulling heavy equipment than 2003 BMW 645.
Compare all specifications:
| 2003 BMW 645 | 2008 Mercedes-Benz R | |
| Make | BMW | Mercedes-Benz |
| Model | 645 | R |
| Year Released | 2003 | 2008 |
| Body Type | Convertible | Minivan |
| Engine Position | Front | Front |
| Engine Size | 4398 cc | 6208 cc |
| Engine Cylinders | 8 cylinders | 8 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 321 HP | 503 HP |
| Engine RPM | 6100 RPM | 6800 RPM |
| Torque | 450 Nm | 630 Nm |
| Torque RPM | 3600 RPM | 5200 RPM |
| Engine Bore Size | 92 mm | 102.2 mm |
| Engine Stroke Size | 82.7 mm | 94.6 mm |
| Engine Compression Ratio | 10.5:1 | 11.3:1 |
| Top Speed | 250 km/hour | 250 km/hour |
| Acceleration 0-100mph | 6.2 seconds | 5.1 seconds |
| Drive Type | Rear | 4WD |
| Transmission Type | Automatic | Automatic |
| Number of Seats | 4 seats | 6 seats |
| Number of Doors | 2 doors | 5 doors |
| Vehicle Weight | 1895 kg | 2375 kg |
| Vehicle Length | 4830 mm | 5160 mm |
| Vehicle Width | 1860 mm | 1930 mm |
| Vehicle Height | 1380 mm | 1640 mm |
| Wheelbase Size | 2790 mm | 3220 mm |
| Fuel Consumption | 8.5 L/100km | 14.9 L/100km |
| Fuel Consumption City | 16.8 L/100km | 19.8 L/100km |
| Fuel Consumption Overall | 11.5 L/100km | 16.5 L/100km |
| Fuel Tank Capacity | 70 L | 80 L |
