2009 BMW Z4 vs. 2013 BMW 6 series
To start off, 2013 BMW 6 series is newer by 4 year(s). Which means there will be less support and parts availability for 2009 BMW Z4. In addition, the cost of maintenance, including insurance, on 2009 BMW Z4 would be higher. At 4,395 cc (8 cylinders), 2013 BMW 6 series is equipped with a bigger engine. In terms of performance, 2013 BMW 6 series (437 HP @ 5500 RPM) has 102 more horse power than 2009 BMW Z4. (335 HP @ 7900 RPM) In normal driving conditions, 2013 BMW 6 series should accelerate faster than 2009 BMW Z4. With that said, vehicle weight also plays an important factor in acceleration. 2013 BMW 6 series weights approximately 699 kg more than 2009 BMW Z4. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 2013 BMW 6 series is all wheel drive (AWD), it will have significant more traction and grip than 2009 BMW Z4. In wet, icy, snow, or gravel driving conditions, 2013 BMW 6 series 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, 2013 BMW 6 series (651 Nm @ 4500 RPM) has 336 more torque (in Nm) than 2009 BMW Z4. (315 Nm @ 2750 RPM). This means 2013 BMW 6 series will have an easier job in driving up hills or pulling heavy equipment than 2009 BMW Z4.
Compare all specifications:
| 2009 BMW Z4 | 2013 BMW 6 series | |
| Make | BMW | BMW |
| Model | Z4 | 6 series |
| Year Released | 2009 | 2013 |
| Body Type | Convertible | Coupe |
| Engine Position | Front | Front |
| Engine Size | 2996 cc | 4395 cc |
| Engine Cylinders | 6 cylinders | 8 cylinders |
| Engine Type | in-line | V |
| Valves per Cylinder | 4 valves | 4 valves |
| Horse Power | 335 HP | 437 HP |
| Engine RPM | 7900 RPM | 5500 RPM |
| Torque | 315 Nm | 651 Nm |
| Torque RPM | 2750 RPM | 4500 RPM |
| Engine Compression Ratio | 12.0:1 | 10.0 :1 |
| Fuel Type | Gasoline | Gasoline |
| Top Speed | 244 km/hour | 250 km/hour |
| Acceleration 0-100mph | 6.2 seconds | 4.5 seconds |
| Drive Type | Rear | AWD |
| Transmission Type | Automatic | 8-speed shiftable automatic |
| Number of Seats | 2 seats | 4 seats |
| Number of Doors | 2 doors | 2 doors |
| Vehicle Weight | 1310 kg | 2009 kg |
| Vehicle Length | 4100 mm | 5009 mm |
| Vehicle Width | 1790 mm | 2081 mm |
| Vehicle Height | 1310 mm | 1392 mm |
| Wheelbase Size | 2500 mm | 2968 mm |
| Fuel Tank Capacity | 55 L | 70 L |
