How it works: four-valve versus two-valve engines

Your engine is composed of many moving parts and pieces. In order to move through the four stages of internal combustion, all of these bits and bobs are quite necessary. Some engines, however, take advantage of squeezing in a few more parts where they can. One area where this is seen often is in extra intake and exhaust valves. Why does it matter... How it works: four-valve versus two-valve engines