Any engine, whether gasoline or diesel, requires compression to operate. The process of compression confines and presses a mixture of air and fuel into a small volume within the area of the engine’s cylinder. This process presses together all the molecules under very high pressure. Since the gasoline engine has a spark plug, only moderate compression is enough, requiring about 140-160 pounds per square inch (PSI).
You may have heard the term “valve job” because older engines frequently needed their valves reconditioned. You rarely hear about valve problems in today’s engines because modern OHC engines have fewer components to wear out […]