2008 BMW X5 vs. 1981 BMW 725
To start off, 2008 BMW X5 is newer by 27 year(s). Which means there will be less support and parts availability for 1981 BMW 725. In addition, the cost of maintenance, including insurance, on 1981 BMW 725 would be higher. At 4,799 cc (8 cylinders), 2008 BMW X5 is equipped with a bigger engine. In terms of performance, 2008 BMW X5 (350 HP @ 6300 RPM) has 202 more horse power than 1981 BMW 725. (148 HP @ 5500 RPM). In normal driving conditions, 2008 BMW X5 should accelerate faster than 1981 BMW 725.
Because 2008 BMW X5 is four wheel drive (4WD), it will have significant more traction and grip than 1981 BMW 725. In wet, icy, snow, or gravel driving conditions, 2008 BMW X5 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 BMW X5 (475 Nm @ 3400 RPM) has 260 more torque (in Nm) than 1981 BMW 725. (215 Nm @ 4000 RPM). This means 2008 BMW X5 will have an easier job in driving up hills or pulling heavy equipment than 1981 BMW 725.
Compare all specifications:
| 2008 BMW X5 | 1981 BMW 725 | |
| Make | BMW | BMW |
| Model | X5 | 725 |
| Year Released | 2008 | 1981 |
| Body Type | SUV | Sedan |
| Engine Position | Front | Front |
| Engine Size | 4799 cc | 2493 cc |
| Engine Cylinders | 8 cylinders | 6 cylinders |
| Engine Type | V | in-line |
| Valves per Cylinder | 4 valves | 2 valves |
| Horse Power | 350 HP | 148 HP |
| Engine RPM | 6300 RPM | 5500 RPM |
| Torque | 475 Nm | 215 Nm |
| Torque RPM | 3400 RPM | 4000 RPM |
| Engine Bore Size | 93 mm | 86 mm |
| Engine Stroke Size | 88.3 mm | 71.6 mm |
| Engine Compression Ratio | 10.5:1 | 9.6:1 |
| Fuel Type | Gasoline - Premium | Gasoline |
| Drive Type | 4WD | Rear |
| Number of Seats | 5 seats | 5 seats |
| Number of Doors | 5 doors | 4 doors |
| Vehicle Length | 4860 mm | 4870 mm |
| Vehicle Width | 1940 mm | 1810 mm |
| Vehicle Height | 1740 mm | 1440 mm |
| Wheelbase Size | 2940 mm | 2810 mm |
