What does L4 and L3 mean in engines?

[McCamilla]

Engine L3 refers to an inline 3-cylinder engine, while L4 refers to an inline 4-cylinder engine. The specific details are as follows: 1. Introduction to engines: An engine is a machine that converts other forms of energy into mechanical energy, including internal combustion engines (such as gasoline engines), external combustion engines (such as Stirling engines and steam engines), and electric motors. For example, an internal combustion engine typically converts chemical energy into mechanical energy. The term 'engine' can refer to both the power-generating device and the entire machine that includes the power device (e.g., gasoline engines, aircraft engines). 2. Types of engines: Inline engine: All its cylinders are arranged side by side in a single plane. Its cylinder block and crankshaft have a simple structure, and it uses a single cylinder head, resulting in lower manufacturing costs, high stability, good low-speed torque characteristics, low fuel consumption, and compact size, making it widely used. The drawback is relatively lower power output. 'Inline' can be represented by the letter 'L,' followed by the number of cylinders to form the engine code. Modern vehicles mainly feature L3, L4, L5, and L6 type engines.