The exhaust stroke is the fourth and last one in the cycle: the piston moves up to TDC, pushing burnt gases out of the cylinder. This is commonly how modern combustion engines work. Some engines ...

In the video after the break, [Brick Technology] uses LEGO to gain some practical insight into the world of piston engine design, from single-cylinder all the way up to radial twelve-cylinder engines.

starts with the piston at the top of the cylinder ... the combustion products are expelled from the cylinder. The sequence shown on the next page represents this behavior for a Mitsubishi direct ...