Recent media reports have described a 1.9 litre diesel engine with 210 horsepower, or equivalently, 82 kW/litre. Is it possible to produce the power without CGI?

Shareholder, Staffan Nordberg

Unfortunately, it is not possible to comment on only one aspect of an engine. Modern engines are complex components that must be analysed as complete units. The important factors in evaluating an engine include not only the performance, but also the size, weight, durability and the method of measuring the performance.

Our shareholders may recall the analogy of suspending a heavy statue from the ceiling of a museum. For this, it is possible to use either aluminium or iron (steel) wires. The only difference will be the size and number of wires required. If the engineers decide to use aluminium wires, they will either need twice as many wires or, a similar number of thicker wires. The combinations, and thus the number of possible solutions, are endless. The same is true for the engine block. It is possible to produce the block in aluminium, grey iron or CGI. The ultimate decision must be based on a combination of factors including the size (packaging constraints in the vehicle), weight, cost, availability of existing manufacturing facilities and image. As we described in the “Five Waves”, the different mechanical loading patterns for V-engines and in-line engines also factors into the material requirements. In our opinion CGI provides an attractive and competitive solution to the total requirements of a modern internal combustion engine.

Another important consideration is durability. Every OEM requires its engines to pass an exhaustive series of durability tests. These laboratory bench tests are conducted at extreme operating conditions for prolonged periods, typically around 1000 hours. Passing these tests ensures that the engine design incorporates an adequate safety margin in relation to normal road use. Surprisingly, it is not sports cars that most closely approach the durability test conditions, but rather, heavily loaded transit vans that drive for prolonged period on open highways. The classical example is for mid-sized commercial vehicles that transport newspapers overnight between European cities. For some production vehicles, the manufacturer may release engines that do not fully satisfy durability requirements in the understanding that the in-service duty-cycle will be less severe than the durability test.

Finally, we must consider the method of measuring the performance, which does vary in the industry.

Overall, it is clear that CGI provides design and performance advantages relative to the conventional engine materials, grey iron and aluminium. At the same time, we must recognise that, given a task from management, a good engineering team can find a variety of solutions, especially for niche applications. From our perspective, we should focus on the overall trend rather than specific engine examples.