What should the engine ignition advance be in degrees?

[ClaraFitz]

Engine ignition advance should be between 6 to 12 degrees. The ignition advance angle refers to the crankshaft rotation angle from the ignition moment until the piston reaches the top dead center of compression. The ignition advance angle that enables the engine to achieve optimal power performance, fuel economy, and emissions is called the optimal ignition advance angle. The main factors affecting ignition advance are engine speed and the combustion speed of the air-fuel mixture. As engine speed increases, the time required to rotate through the same angle decreases, requiring a larger advance angle to achieve the corresponding advance time. The combustion speed of the air-fuel mixture is related to mixture composition, engine design, and other factors.