1968 Opel Diplomat vs. 1966 Vauxhall Viscount
To start off, 1968 Opel Diplomat is newer by 2 year(s). Which means there will be less support and parts availability for 1966 Vauxhall Viscount. In addition, the cost of maintenance, including insurance, on 1966 Vauxhall Viscount would be higher. At 5,354 cc (8 cylinders), 1968 Opel Diplomat is equipped with a bigger engine. In terms of performance, 1968 Opel Diplomat (227 HP @ 4700 RPM) has 105 more horse power than 1966 Vauxhall Viscount. (122 HP @ 4600 RPM). In normal driving conditions, 1968 Opel Diplomat should accelerate faster than 1966 Vauxhall Viscount. With that said, vehicle weight also plays an important factor in acceleration. 1968 Opel Diplomat weights approximately 310 kg more than 1966 Vauxhall Viscount. So despite on having greater horse power, its additional weight may have an impact towards its acceleration in comparison.
Both vehicles are rear wheel drive (RWD) - it offers better handling in dry conditions; in addition, if you are looking to drift, both vehicles do the job better than front wheel drive vehicles. 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, 1968 Opel Diplomat (427 Nm @ 3000 RPM) has 186 more torque (in Nm) than 1966 Vauxhall Viscount. (241 Nm @ 2400 RPM). This means 1968 Opel Diplomat will have an easier job in driving up hills or pulling heavy equipment than 1966 Vauxhall Viscount. 1968 Opel Diplomat has automatic transmission and 1966 Vauxhall Viscount has manual transmission. 1966 Vauxhall Viscount will offer better control over acceleration and deceleration in addition to better fuel efficiency overall. 1968 Opel Diplomat will be easier to drive especially in heavy traffic.
Compare all specifications:
| 1968 Opel Diplomat | 1966 Vauxhall Viscount | |
| Make | Opel | Vauxhall |
| Model | Diplomat | Viscount |
| Year Released | 1968 | 1966 |
| Engine Position | Front | Front |
| Engine Size | 5354 cc | 3294 cc |
| Engine Cylinders | 8 cylinders | 6 cylinders |
| Engine Type | V | in-line |
| Horse Power | 227 HP | 122 HP |
| Engine RPM | 4700 RPM | 4600 RPM |
| Torque | 427 Nm | 241 Nm |
| Torque RPM | 3000 RPM | 2400 RPM |
| Engine Bore Size | 101.6 mm | 92 mm |
| Engine Stroke Size | 82.6 mm | 82.6 mm |
| Engine Compression Ratio | 10.5:1 | 8.5:1 |
| Drive Type | Rear | Rear |
| Transmission Type | Automatic | Manual |
| Number of Doors | 4 doors | 4 doors |
| Vehicle Weight | 1690 kg | 1380 kg |
| Vehicle Length | 4960 mm | 4760 mm |
| Vehicle Width | 1910 mm | 1780 mm |
| Vehicle Height | 1450 mm | 1430 mm |
| Wheelbase Size | 2850 mm | 2740 mm |
