1991 Opel Calibra vs. 1951 Rover P4
To start off, 1991 Opel Calibra is newer by 40 year(s). Which means there will be less support and parts availability for 1951 Rover P4. In addition, the cost of maintenance, including insurance, on 1951 Rover P4 would be higher. At 2,103 cc (6 cylinders), 1951 Rover P4 is equipped with a bigger engine. In terms of performance, 1991 Opel Calibra (201 HP @ 5600 RPM) has 126 more horse power than 1951 Rover P4. (75 HP @ 4200 RPM). In normal driving conditions, 1991 Opel Calibra should accelerate faster than 1951 Rover P4. With that said, vehicle weight also plays an important factor in acceleration. 1991 Opel Calibra weights approximately 33 kg more than 1951 Rover P4. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Because 1991 Opel Calibra is four wheel drive (4WD), it will have significant more traction and grip than 1951 Rover P4. In wet, icy, snow, or gravel driving conditions, 1991 Opel Calibra 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, 1991 Opel Calibra (280 Nm @ 2400 RPM) has 130 more torque (in Nm) than 1951 Rover P4. (150 Nm @ 2500 RPM). This means 1991 Opel Calibra will have an easier job in driving up hills or pulling heavy equipment than 1951 Rover P4.
Compare all specifications:
| 1991 Opel Calibra | 1951 Rover P4 | |
| Make | Opel | Rover |
| Model | Calibra | P4 |
| Year Released | 1991 | 1951 |
| Engine Position | Front | Front |
| Engine Size | 1998 cc | 2103 cc |
| Engine Cylinders | 4 cylinders | 6 cylinders |
| Engine Type | in-line | in-line |
| Valves per Cylinder | 4 valves | 2 valves |
| Horse Power | 201 HP | 75 HP |
| Engine RPM | 5600 RPM | 4200 RPM |
| Torque | 280 Nm | 150 Nm |
| Torque RPM | 2400 RPM | 2500 RPM |
| Engine Compression Ratio | 9.0:1 | 7.3:1 |
| Fuel Type | Gasoline | Gasoline |
| Drive Type | 4WD | Rear |
| Number of Seats | 4 seats | 5 seats |
| Number of Doors | 2 doors | 4 doors |
| Vehicle Weight | 1423 kg | 1390 kg |
| Vehicle Length | 4500 mm | 4590 mm |
| Vehicle Width | 1700 mm | 1670 mm |
| Vehicle Height | 1610 mm | 1620 mm |
| Wheelbase Size | 2450 mm | 2830 mm |
| Fuel Tank Capacity | 40 L | 52 L |
