THE BEECHMONT CREST AUTOMOTIVE LEARNING ZONE

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IGNITION TIMING

Ignition timing refers to when the spark plugs fire in relation to the position of the engine pistons. Ignition timing varies with engine speed and load. 

Timing advance is necessary at high engine speeds. Timing advance takes place when the spark plugs fire early in the engine’s compression stroke. The early firing of the spark plugs allows more time for combustion.  

Timing retard is necessary at low engine speeds. Timing retard is a delayed firing of the spark plugs in relation to piston position. Timing retard prevents engine ping---which occurs when excess fuel is burnt on the compression stroke.