2005 BMW X5 vs. 1981 Pontiac Firebird
To start off, 2005 BMW X5 is newer by 24 year(s). Which means there will be less support and parts availability for 1981 Pontiac Firebird. In addition, the cost of maintenance, including insurance, on 1981 Pontiac Firebird would be higher. At 5,012 cc (8 cylinders), 1981 Pontiac Firebird is equipped with a bigger engine. In terms of performance, 2005 BMW X5 (215 HP @ 4000 RPM) has 70 more horse power than 1981 Pontiac Firebird. (145 HP @ 3800 RPM). In normal driving conditions, 2005 BMW X5 should accelerate faster than 1981 Pontiac Firebird. With that said, vehicle weight also plays an important factor in acceleration. 2005 BMW X5 weights approximately 628 kg more than 1981 Pontiac Firebird. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2005 BMW X5 is four wheel drive (4WD), it will have significant more traction and grip than 1981 Pontiac Firebird. In wet, icy, snow, or gravel driving conditions, 2005 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, 2005 BMW X5 (520 Nm @ 2000 RPM) has 196 more torque (in Nm) than 1981 Pontiac Firebird. (324 Nm @ 2400 RPM). This means 2005 BMW X5 will have an easier job in driving up hills or pulling heavy equipment than 1981 Pontiac Firebird.
Compare all specifications:
| 2005 BMW X5 | 1981 Pontiac Firebird | |
| Make | BMW | Pontiac |
| Model | X5 | Firebird |
| Year Released | 2005 | 1981 |
| Body Type | SUV | Coupe |
| Engine Position | Front | Front |
| Engine Size | 2926 cc | 5012 cc |
| Engine Cylinders | 6 cylinders | 8 cylinders |
| Engine Type | in-line | V |
| Valves per Cylinder | 4 valves | 2 valves |
| Horse Power | 215 HP | 145 HP |
| Engine RPM | 4000 RPM | 3800 RPM |
| Torque | 520 Nm | 324 Nm |
| Torque RPM | 2000 RPM | 2400 RPM |
| Engine Bore Size | 84 mm | 95 mm |
| Engine Stroke Size | 90 mm | 88.4 mm |
| Engine Compression Ratio | 18.0:1 | 8.6:1 |
| Fuel Type | Diesel | Gasoline |
| Top Speed | 210 km/hour | 160 km/hour |
| Drive Type | 4WD | Rear |
| Transmission Type | Manual | Manual |
| Number of Seats | 5 seats | 4 seats |
| Number of Doors | 5 doors | 2 doors |
| Vehicle Weight | 2170 kg | 1542 kg |
| Vehicle Length | 4670 mm | 5040 mm |
| Vehicle Width | 1880 mm | 1860 mm |
| Vehicle Height | 1720 mm | 1260 mm |
| Wheelbase Size | 2830 mm | 2750 mm |
| Fuel Tank Capacity | 93 L | 79 L |
