With the push for ever-improved engine efficiency in general, and a specific drive toward increased torque and power output from race engines, there has been much work done on coating piston skirts to reduce frictional losses. There are various options available, from resin-bonded polymers to DLC. However, other piston coatings can also help us achieve our goals, although by very different means. Piston crown coatings are used for various reasons but, as we shall find out, there are...
When we hear the word 'anodising', it is generally a process we associate with aluminium components. Most of us will be familiar with decorative coloured anodic finishes and the much thicker 'hard' anodising treatments that are often applied to mechanical parts. However, a small number of other materials may be anodised; these are zinc, magnesium and titanium. The anodising of titanium is certainly less widespread than anodising aluminium, but it can fulfil an important role...
When performing any measurement, whether it be gauging the clearance on a component or performing a power run on a dyno, you want to have accuracy and repeatability. But what do these terms actually mean? People often get the two confused, and replace one with the other, but from a testing standpoint the differences in their meaning and impact on test results is considerable. The dictionary definition of accuracy is: "The degree to which the result of a measurement, calculation, or...
Surface finishing and coating processes continue to make their mark on the motorsport arena, enabling engineers to improve the properties of components that experience direct metal-on-metal contact. NASCAR is no exception to this and, within a very tight regulatory framework, teams are keen to gain any advantage they can. Power levels are very closely matched between different manufacturers' engines, so very small gains in power can be decisive. This does not necessarily mean...
If we look at a production engine from a roadcar, the chances are high that the cams will be driven by a toothed belt, whether the engine is overhead camshaft or overhead valve (pushrod). If we look at an engine from a motorcycle, the camshaft drive is often internal and the drive to the camshaft from the crank is taken care of by a special type of chain. The fact that there are discrete timing elements on both of these components - as in teeth on the belt and links on the chain - means...