2008 BMW Z4 vs. 2005 Fiat Siena
To start off, 2008 BMW Z4 is newer by 3 year(s). Which means there will be less support and parts availability for 2005 Fiat Siena. In addition, the cost of maintenance, including insurance, on 2005 Fiat Siena would be higher. At 2,994 cc (6 cylinders), 2008 BMW Z4 is equipped with a bigger engine. In terms of performance, 2008 BMW Z4 (215 HP @ 6250 RPM) has 91 more horse power than 2005 Fiat Siena. (124 HP @ 4000 RPM). In normal driving conditions, 2008 BMW Z4 should accelerate faster than 2005 Fiat Siena. With that said, vehicle weight also plays an important factor in acceleration. 2008 BMW Z4 weights approximately 300 kg more than 2005 Fiat Siena. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2008 BMW Z4 is rear wheel drive (RWD), it offers better handling in dry conditions; in addition, if you are looking to drift, it will be much easier to do with 2008 BMW Z4. However, in wet, icy, snow, or gravel driving conditions, 2005 Fiat Siena, being front wheel drive (FWD), will offer much better control with better grip. 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 Z4 (251 Nm @ 2750 RPM) has 111 more torque (in Nm) than 2005 Fiat Siena. (140 Nm @ 4000 RPM). This means 2008 BMW Z4 will have an easier job in driving up hills or pulling heavy equipment than 2005 Fiat Siena.
Compare all specifications:
| 2008 BMW Z4 | 2005 Fiat Siena | |
| Make | BMW | Fiat |
| Model | Z4 | Siena |
| Year Released | 2008 | 2005 |
| Body Type | Convertible | Sedan |
| Engine Position | Front | Front |
| Engine Size | 2994 cc | 1585 cc |
| Engine Cylinders | 6 cylinders | 4 cylinders |
| Engine Type | in-line | in-line |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 215 HP | 124 HP |
| Engine RPM | 6250 RPM | 4000 RPM |
| Torque | 251 Nm | 140 Nm |
| Torque RPM | 2750 RPM | 4000 RPM |
| Engine Bore Size | 85.1 mm | 86.4 mm |
| Engine Stroke Size | 88.1 mm | 67.4 mm |
| Drive Type | Rear | Front |
| Transmission Type | Manual | Manual |
| Number of Seats | 2 seats | 5 seats |
| Number of Doors | 2 doors | 4 doors |
| Vehicle Weight | 1395 kg | 1095 kg |
| Wheelbase Size | 2500 mm | 2450 mm |
| Fuel Tank Capacity | 55 L | 47 L |
