One of the trends for development of internal combustion engine is downsizing, which in its final form leads to reduction of fuel consumption and limitation of carbon dioxide concentration in the exhaust gases. The obvious effect of reducing the volume of a cylinder is to reduce the dimensions of the various components, e.g. piston with rings and pin, connecting rod, crankshaft, engine block etc. Changes of geometric dimensions also affect the change in mass of each element and consequently − the whole engine. Expected weight reduction will be a benefit in considering downsizing techniques as another significant development trend in automotive applications associated with a reduction in the weight of the complete vehicle – called “light weight vehicle”. The paper discusses the various forms of downsizing (by stroke, by diameter and mix) and their impacts on the changes in engine mass. The engine Subaru Flat 4, constructed with standard components in terms of design and materials was tested by virtual recognition in mass changes. Original drawings of components and sets have been simplified by for example does not account for chamfers and chops. When calculating also omitted the weight of typical accessories (e.g. fuel lines or electronic components), assuming that each considered option has the same equipment. The highest change in the weight of minus 7.27 % relative to the standard engine was done with downsizing by diameter and smallest one (-6.09 %) by downsizing mix.
- combustion engine
- weight change