AFR understanding

[Green7mgte]

AFR understanding:
my pieces are starting to fall into place and thus beginning my build.
but as always before I remove one screw on my supra I iron out all the details of the job ahead. One thing I'm most concerned about is understanding Air to fuel ratio in the 7mgte, along with modifying timing. I would just like some feedback, link to sources and info pages for this mater. So I can go into my build with a good knowledgeable background to fall onto, once I start to tune.

thanks for the assistance in pointing me in the right direction.

just a couple general questions
what is the afr goal for at cruise? what about under boost with the karman type NA engines.
is a tad on the rich side a safer buffer? if so by how much?
is regular tested gass fine? since ive been running it forever? or would you recommend the high test pump gass?

also, just a quick question about safc1 tuning
ive read about the high and low throttle points. each setting is different per your build i understand.
is the afr tied into the open loop vs closed loop throttle setting? just a bit boggled on that part.