Advancing/ Retarding Ignition Timing Information

[xlMcMlx DsM]

My Powertrain Management teacher isn't too in tune with his ignition timing and how it affects power. And I'd like to read up on it some more. I searched around here, but couldn't really find much on the effect of advancing or retarding. I have a basic understanding, but If anyone happens to have a link to someplace that has lots of info on ignition timing, It'd be appreciated. Or someone who is 100% positive they know, can write a good, detailed description of their knowledge. Thanks.

 

[kahl23]

It's from a honda board but still should answer your question.

Advance Ignition Timing: What Happens ? - Team Integra

 

[Defiant]

Remember riding a bicycle? Remember the time you tried for the coaster brake while the pedals were up-and-down, and not being able to back-pedal to use them? The pedals are your pistons. For a fair bit of the crank's rotating -oh, twenty degrees or so- at both top and bottom of the stroke, they're barely moving.
Burning the fuel -I hope your instructor has drilled-home that it's burning and not exploding- takes time. Starting the fire as the piston's coming "up" -advancing the spark timing- while it's still in that "dead space" makes sure that the most heat energy is being imparted to the piston just at the point where it'll carry the most power to the crank, just like you press hardest on the pedal on a bike to get up a hill, in the range from about 30°~150°.
As the crank speed increases, and piston and valve events speed up, the burning speed of your fuel doesn't much change (all under the influence of compression ratio, engine and combustion chamber temperatures, and, of course, "stuff"), so in order to have the most energy conversion at that sweet spot in the crank position, timing has to be advanced.
This is interesting enough at 750 RPM. It gets more interesting at 7500. And god knows what is going on inside motorcycle and F1 engines that are turning 20,000 RPM.

 

[xlMcMlx DsM]

Good like Kahl, And thanks Defiant, some good info and the analogy is pretty good, too.