2006 BMW 645 vs. 1993 BMW 856
To start off, 2006 BMW 645 is newer by 13 year(s). Which means there will be less support and parts availability for 1993 BMW 856. In addition, the cost of maintenance, including insurance, on 1993 BMW 856 would be higher. At 5,576 cc (12 cylinders), 1993 BMW 856 is equipped with a bigger engine. In terms of performance, 1993 BMW 856 (376 HP @ 5300 RPM) has 48 more horse power than 2006 BMW 645. (328 HP @ 6100 RPM) In normal driving conditions, 1993 BMW 856 should accelerate faster than 2006 BMW 645. With that said, vehicle weight also plays an important factor in acceleration. 1993 BMW 856 weights approximately 29 kg more than 2006 BMW 645. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
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, 1993 BMW 856 (550 Nm @ 4000 RPM) has 100 more torque (in Nm) than 2006 BMW 645. (450 Nm @ 3600 RPM). This means 1993 BMW 856 will have an easier job in driving up hills or pulling heavy equipment than 2006 BMW 645.
Compare all specifications:
| 2006 BMW 645 | 1993 BMW 856 | |
| Make | BMW | BMW |
| Model | 645 | 856 |
| Year Released | 2006 | 1993 |
| Body Type | Convertible | Coupe |
| Engine Position | Front | Front |
| Engine Size | 4398 cc | 5576 cc |
| Engine Cylinders | 8 cylinders | 12 cylinders |
| Engine Type | V | V |
| Valves per Cylinder | 2 valves | 2 valves |
| Horse Power | 328 HP | 376 HP |
| Engine RPM | 6100 RPM | 5300 RPM |
| Torque | 450 Nm | 550 Nm |
| Torque RPM | 3600 RPM | 4000 RPM |
| Engine Bore Size | 92 mm | 86 mm |
| Engine Stroke Size | 83 mm | 80 mm |
| Engine Compression Ratio | 10.0:1 | 9.8:1 |
| Fuel Type | Gasoline | Gasoline |
| Drive Type | Rear | Rear |
| Transmission Type | Manual | Manual |
| Vehicle Weight | 1836 kg | 1865 kg |
| Vehicle Length | 4830 mm | 4790 mm |
| Vehicle Width | 1860 mm | 1860 mm |
| Vehicle Height | 1380 mm | 1350 mm |
| Wheelbase Size | 2790 mm | 2690 mm |
