I was wondering if someone could explain this better to me, benefits etc...

ie retarding and advancing the timing.

 

Ignition timing is a LONG story. I suggest you pick up Modern Engine Tuning by A. Graham Bell. It does a much better job of covering ignition timing that I possibly could, in addition to covering just about every other aspect of engine performance.

 

ignition timing is simple !!!

its just like the human brain.. some are advanced, and some are retarded ! !

get it ? j/k. tongue.gif

 

Basically as engine speed increases it gives less time for the fuel to ignite and the flame front to travel. So therefore the fuel ingnition starts to happen later in the cycle. When you advance the timing your bringing that fuel ignition closer back to TDC. One of the few times that you use ignition retard in when your using some sort of power adder, such as Nitrous. The ignition retard is usually helpful on oem ecu's because the timing curve is preset and therefore you have to over ride it. There has been some recent discusion on the debate to retard the timing and nitrous. When you retard timing basically your basically loosing some of your peak cylinder pressure and negating some of the effects of nitrous. One thing on the negative side of advancing is that if there is a presure spike when the fuel is ignited, such from a power adder you can get what is called bearing chatter. It is where you are applying a axial force directly down on the bearing surface and destroying your hydrodynamic wedge. That is why timing is so critical, bearing chatter can even happen when running NA. Another thing as fuel and air density increases the acceleration rate of the flame front increases.

[ March 10, 2002, 08:59 PM: Message edited by: HRD_Tiburon ]