An engineer should not only have solid grounding in the fundamentals of his discipline but an interest in history too. A thorough understanding of the principles involved in product design is, I would have thought, an absolute necessity but an appreciation of all that has gone before is as equally valuable. So when other people are perhaps relaxing or enjoying the fruits of their labour I often prefer to saunter around some of the smaller transport museums in this land. On one occasion hidden behind a glass case I came Read more…

A major consideration of any engine designer right from the outset is that of the cooling system. Even in the most efficient of gasoline race engines, only 35% of the fuel energy available is converted into mechanical power. The rest, something like 850kW from an engine delivering 450kW, is converted into heat which will need to be dissipated into the surrounding atmosphere. Putting it into perspective that’s something like 280+, 3kW electric fires worth of heat, approximately half of which will go out through the exhaust system with the remainder - around 400kW rejected Read more…

The trouble with advancing years, or so I was always told, was that you can always remember how it used to be. In the dim and distant past, it seemed to be much more fun (even though it probably wasn’t) and if the job couldn’t be precise then we always made it as accurate as we could somehow adapting the product to the limitations of the manufacturing process.

A typical case of this, I was reminded recently, was in the casting of cylinder heads and crankcases. In those days and I am only talking about the 1960s here Read more…

In the inexorable search for reduced weight, the various alloys of aluminium are most commonly used for high performance gasoline engines. Where peak firing loads are higher, for example as in the case of a modern direct injected diesel engine, this may need to be some form of S.G. (spheroidal graphite) iron. With its excellent flow properties in the molten state, sections can be cast much thinner than other cast irons and thus the disadvantage of a density nearer 7 gm/cm3 can, to a certain extent, be overcome. But when ultra low weight has to be the deciding factor then the only realistic choice is that of magnesium. Read more…

If you’ve been in the automotive industry for any length of time you will by now have the words “higher performance, less weight at a cheaper price” more or less burned into the inner soul of your psyche. Since weight is the ultimate destroyer of any performance improvement, it nevertheless rankled if ever we were to reduce the weight of the power unit by some paltry amount someone always managed to find room for yet one more electric motor in the seat! Be that as it may and despite the extra level of driver (or passenger) comfort afforded, the inexorable search for lighter, more powerful engines goes on. Read more…

Isn’t it strange how solving one issue in racing can sometimes lead to solving a different problem in production engines many years later. The evolution of the main bearing cap springs to mind.

It was while examining a cylinder block prior to rebuilding a classic engine that made me reflect on how far, in terms of technology modern road vehicle engines have come. The crankcase in question was a five bearing four cylinder unit of 1970s origin and having a relatively undersquare bore/stroke ratio would rev regularly up to 9000 rpm. Read more…

Many years ago, as a young and somewhat naive apprentice, I was told by my training supervisor to go to the engineering stores and ask for ‘a long wait.’ Thinking that this was some form of specialised turning tool, I dutifully did as requested only to be told after 10 minutes at the counter “You’ve had your long wait, now clear off!” Engineers and former apprentices of a certain age might recognise my continuing embarrassment. So when the idea of the ‘long bolt’ was first suggested it took some time to dispel thoughts of a possible prank Read more…

The process of engineering design is very much a compromise and sometimes, even with modern computerised techniques, several iterations may be required before the final, optimised product evolves. The design of a modern cylinder head can be a perfect example of this. Although four valves per cylinder with a central spark plug is ubiquitous in gasoline engines, as the included angle of the intake and exhaust valves becomes smaller, the architecture of the valve train and space for the fasteners to assemble it all becomes much more critical. This is especially the case when direct acting mechanical buckets (DAMB) are used.

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There is no doubt about it, the engine in your average family saloon car has come on a long way in the last 30 years. When once we struggled to get 100 bhp out of a 1.6 litre engine, today 100 bhp per litre is now easily achievable. Such are the improvements to the humblest of engines, the latest 1.6 litre Duratec although rated at 100PS (98.6 bhp) in the Ford Fiesta produces the thick end of 160 with only slight changes to the cam and induction / exhaust system. But for 200 bhp per litre it’s a different matter.

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The GM Gen-4 Small Block pushrod V8 engine family (aka LS-X) is growing in popularity and in application as a racing engine as well as a high performance powerplant for roadgoing cars. The basic LS design contains several significant improvements over the ubiquitous Gen-1 engine, and there is a growing abundance of high-quality aftermarket components which add even more features to the design.

One of the newest and most impressive of those components is the aluminium LS engine block announced by the RHS division of the Comp Performance Group at the 2008 PRI Show. This block was designed from the outset to include as many desirable high-performance features as possible. Read more…