Inline-four engine
inline piston engine with four cylinders / From Wikipedia, the free encyclopedia
The Inline-four engine or Straight-four is an internal combustion engine with four cylinders. All four cylinders are mounted in a straight line along one crankshaft. It can be powered by different types of fuels, including gasoline, diesel and natural gas.
The single bank of cylinders may be in a vertical direction (straight up), or at an angle. When the cylinders are mounted at an angle, it is sometimes called a slant-four. When listed as an abbreviation, an inline-four engine is listed either as I4 or L4 (for longitudinal). L4 is often used to avoid confusion between the digit 1 and the letter I.
The inline-four layout is a mechanically simple engine. It has a natural basic engine balance. It is smoother than one, two, and three cylinder engines. This makes it popular for economy cars.[1] It does have a problem with secondary engine balance. This causes minor vibrations in smaller engines. These vibrations become worse as engine size and power increase. The more powerful engines used in larger cars use a different engine layout to avoid this problem.