1971 BMW Touring vs. 1973 Citroen SM
To start off, 1973 Citroen SM is newer by 2 year(s). Which means there will be less support and parts availability for 1971 BMW Touring. In addition, the cost of maintenance, including insurance, on 1971 BMW Touring would be higher. At 2,670 cc (6 cylinders), 1973 Citroen SM is equipped with a bigger engine. In terms of performance, 1973 Citroen SM (171 HP @ 5500 RPM) has 86 more horse power than 1971 BMW Touring. (85 HP @ 5700 RPM) In normal driving conditions, 1973 Citroen SM should accelerate faster than 1971 BMW Touring. With that said, vehicle weight also plays an important factor in acceleration. 1973 Citroen SM weights approximately 420 kg more than 1971 BMW Touring. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Let's talk about torque, 1973 Citroen SM (237 Nm @ 4000 RPM) has 107 more torque (in Nm) than 1971 BMW Touring. (130 Nm @ 3500 RPM). This means 1973 Citroen SM will have an easier job in driving up hills or pulling heavy equipment than 1971 BMW Touring.
Compare all specifications:
| 1971 BMW Touring | 1973 Citroen SM | |
| Make | BMW | Citroen |
| Model | Touring | SM |
| Year Released | 1971 | 1973 |
| Engine Position | Front | Front |
| Engine Size | 1573 cc | 2670 cc |
| Engine Cylinders | 4 cylinders | 6 cylinders |
| Engine Type | in-line | V |
| Valves per Cylinder | 2 valves | 2 valves |
| Horse Power | 85 HP | 171 HP |
| Engine RPM | 5700 RPM | 5500 RPM |
| Torque | 130 Nm | 237 Nm |
| Torque RPM | 3500 RPM | 4000 RPM |
| Engine Bore Size | 84.1 mm | 87 mm |
| Engine Stroke Size | 71 mm | 75 mm |
| Engine Compression Ratio | 8.6:1 | 9.0:1 |
| Fuel Type | Gasoline | Gasoline |
| Number of Seats | 5 seats | 2 seats |
| Vehicle Weight | 1030 kg | 1450 kg |
| Vehicle Length | 4120 mm | 4900 mm |
| Vehicle Width | 1600 mm | 1850 mm |
| Vehicle Height | 1390 mm | 1330 mm |
| Wheelbase Size | 2510 mm | 2960 mm |
