Here is an animated cutaway model of a typical piston and valve assembly used in combustion engines. This can be used as a great training or teaching aid. It was created in 3DS MAX 2013 and uses standard Mentalray materials which can easily be changed. No bit maps are used on the models for hassle free network rendering. The parts are intelligently named and grouped. When possible, object pivot points are placed where they should be for logical animation and parametric objects are left un-collapsed so that you can adjust and animate them, when desired. This model is ready to be dropped into your scenes and rendered.