What does the ignition advance angle mean?

When the engine (gasoline engine) works, the ignition time has a great influence on the working performance of the engine. Pre-ignition means that the spark plug ignites before the piston reaches the compression top dead center to ignite the combustible mixture in the combustion chamber. The angle of crankshaft rotation from ignition time to piston reaching compression top dead center is called ignition advance angle.

The ignition advance angle that can make the engine get the best power, economy and emission is called the best ignition advance angle.

Extended data:

Factors affecting the optimal ignition advance angle;

1, cylinder temperature and cylinder pressure. The higher the combustion speed, the smaller the ignition advance angle. The factors affecting cylinder temperature and cylinder pressure are: engine compression ratio, air temperature, cylinder temperature and load. Because of this, in the season of temperature change, everyone's car has different performances.

2. Octane number of gasoline. That is, the higher the gasoline brand, the stronger the antiknock ability and the larger the corresponding allowable ignition advance angle.

3. Gas mixing ratio. Too rich and too lean combustion speed is slow, so it is necessary to increase the ignition advance angle. This mainly depends on the throttle opening and altitude.

For unpredictable situations, some cars are also equipped with knock sensors to automatically reduce the ignition advance angle when knocking occurs.

It is difficult to rely on the traditional analog igniter to complete such complex modulation. Only a single igniter can achieve the best ignition advance angle at high speed, accurately and stably.

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