Charge Temp as a factor of ignition advance

Shouldnt IAT/Charge temp be mensioned as well as a 5th factor to influence the ign. adv.? ("The Tuning Process" : "Tuning Ignition"-Video)

or is it a topic of a later more in depth video on ignition timing or fuel delivery strategy?

I guess IAT has a similar effect on ing. timing as shown for rpm - almost linear dependance on ign. adv. as with cooler charge there are more O molecule leading to more fuel needed = more mass needed to be burnd so more time will be needed?

Or more mass being comressed leading to a denser mixure will need burn faster so less time/ ing adv. will be needed???

I'd recon IAT goes down -> Ign. Adv. goes down as well?

AND: IAT goes up -> Ign. Adv. goes down as well to avoid knock?

I'm confues.. i guess the graph will end up looking more lika the VE vs. RPM one?

You raise a reasonable point. In the particular module you're referencing, the intent was to assume a fixed IAT so I was only considering the effect of rpm and load/airmass. Since you've brought it up though, yes the IAT will have an affect on ignition timing requirements however in my own experience this is less significant to our tuning than the other two aspects.

As IAT increases, combustion speed also increases which means we need to retard the ignition timing to achieve MBT. Typically the bigger concern is that as the IAT increases, the engine will become more prone to knock and hence we may need to retard the timing to avoid the engine knocking - This will depend obviously on the particular engine and the fuel we're using.

Thank you Andre.

This topic is also mentiond in one of the AFR modules that I enjoyed some time later. So by the time i got to read your answer I've allready seen the particulaer module and got informed about the effect that you describe.

Onether question:

How can i see if I've already got an answer to a Thread/Question i posted in the Forum?

AND

Is there a list of priority or sequence to which it makes the most sense to watch the courses?

I started with the EFI Basics

than done the AFR one

and am doing the dyno practicle one right now

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The order you've gone through is pretty much ideal :)