In theory at least, an engine bearing – be it big-end or crankshaft main – should be one of the simplest components to lubricate. Separated by a thin film of oil forced into a gap under pressure, when running at a constant rotational speed, the resulting ‘wedge’ of fluid forces the components apart, disengaging both shell and journal asperities. Since there is no contact between bearing and journal, no wear can take place and the power loss in the system is down to...
Much has already been written in these columns about the technicalities of cam design and manufacture. But unless the component is properly installed in the engine so that the intake and exhaust valves are accurately phased to the motion of the piston then much of the effort involved in designing the cam may be completely lost. Rather like a stand-up comedian, when it comes to speaking of camshafts, timing is everything. For most applications I guess it is safest to suggest that, when...
In the past 15 years or so there has been a huge change in the range of coatings for metallic components in motorsport, with many more suppliers and a much wider choice. Before then, and in terms of hard-wearing coatings, these often implied adding a different material such as a hard metal or ceramic to the component’s surface to a significant thickness before grinding back to finished size. Various spraying techniques were commonly used to apply such materials, and they are still in...
There have been a number of RET-Monitor articles on con rod materials over the past few years. The last article to cover steel as a con rod material, in late 2009, discussed the general benefits compared to other materials. In general terms, people have tended to consider steel as the safe option and titanium as the material for the optimum rod if the budget allows. If we decided to look beyond traditional steels for rod manufacture and towards some of the more exotic steels available,...
It is a sad indictment of the spark-ignition engine that, even in its most efficient form, for every horsepower or kilowatt generated, the thermal equivalent of at least two more are lost as heat. And although up to half of this can be conveniently discharged directly into the atmosphere in the form of exhaust gas, the remaining heat – the amount roughly equivalent to the power output of the engine itself– has to be disposed of in other, less convenient ways. As my old...