Although a car properly designed for speed should never have any problems with cooling, there are times when the lack of forward motion can limit the amount of heat dissipated through its radiator. In earlier times, simple two- or four-blade fans would be powered directly via a v-shaped belt from the engine crankshaft, but these days when the cooling limit from the forward motion of the vehicle has been reached, the electric fan normally takes over. Used in competition - for instance in...
While there are reciprocating engines that don't have a crankshaft, these are rare and have generally done little to convince people that we ought to abandon it. The crankshaft, with its eccentric crankpins, is not a straightforward part to make. Evidence for this lies in the small number of manufacturers capable of making top-quality examples. Traditionally, the work involved in producing the basic functional shape of such parts has been done on the lathe. We can imagine taking a...
It doesn't seem that long ago when all that was needed to fire up your racer was to change one set of spark plugs for some 'hotter' ones, once the engine was warmed up and ready to go. The procedure used to be commonplace, and while the one set was rather less than cherished, the racing plugs were treated with respect, cleaned carefully and replaced in their little box ready for the next event. The evolution of the spark plug may have moved on, and many exotic (and some not so...
After having written a number of articles on some interesting engine projects, especially in the field of amateur racing, this article will give some more background on an internal aspect of engine design - cylinder liners. In deciding on the best liner design for an engine, a number of boundary conditions need to be evaluated. First, a conceptual decision needs to be made between whether the engine will use parent bore (bore in the base block or cylinder material), dry liner (liner...
The main disadvantage of a turbocharged engine compared to a naturally aspirated one is poor transient throttle response, commonly referred to as 'turbo lag'. This effect is something that roadcar manufacturers continue to improve with all kinds of clever technology such as variable geometry turbochargers. Turbocharged engines have many advantages. They are compact and, as such, can produce high performance from a physically small and light package. They are typically slightly more...