using 14.047 for desired AFR and not 14.63?

[mr.prick]

I am aware of this. My point being did GM set the PE table up as unusually rich or were they acknowledging the fact that many cars would see E10 and set up PE tables to acknowledge a rich non-ethanol AFR or a damn close PE for E10.

Your guess is as good as mine.
An '02 Fbody Stoich setting is close to gas
and the max PE value is closer to E22 according to the spreadsheet.

A lean stoich for E10 and
and way rich PE for gas.

An '02 Ybody(zo6) seems to be a different story
According to the spreadsheet stoich setting is gas
and PE is right on for E10.



An email to the CEO of GM may get a definitive answer to your question.