The process of setting the time that a spark will occur in the engine combustion chamber (during the power stroke) relative to piston position or crankshaft rotation. Setting the correct ignition timing is crucial in the performance of an engine. The ignition timing affects many variables including engine longevity, fuel economy, and engine power. Modern engines that are controlled by an engine control unit use a computer to control the timing throughout the engine’s RPM range. Older engines that use mechanical spark distributors rely on inertia (by using rotating weights and springs) and manifold vacuum in order to set the ignition timing throughout the engine’s RPM range.
Comments
2 Comments so far
I have an ‘07 Yamaha Fazer 1000 w/ Power Commander. According to Dyno testing the bike has recorded 137HP @10,500RPM in the rear wheel. My mechanic has insisted that I get the Ignition Module too. How would you estimate it to affect performance in relation to the numbers I have mentioned?
[...] or when the spark occurs. It is normally expressed in degrees or millimetres before TDC (see ignition timing and port [...]