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IAT installed. AFRatioEst lean across the board

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
Evan just finished installing an I AT in my car and it's working great. I have noticed, however, that my AFRatioEst is now about 1:1 leaner than before the IAT was installed. It used to track fairly well against the WB, but now, lean.

I'm can't say I'm sure exactly how to sort that out. The AFR in the Maxoct table is correct and tracks with the WB well enough. What other knobs can I turn to get this value back in line with my WB and octane table?
 
Last edited:

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
So I'm guessing (I would italicize "guessing" if I could) that this might have to do with my global fuel adjustments. Currently, my global fuel is sitting at -50.8% . That's a good bit off from the calculated value of -52.63% than my FIC 950's should be at/around. Now I adjusted my global fuel over the last few weeks to get my VE max cell values down below 100. Really a cosmetic adjustment, but was it really...? Could it be that I've adjusted my global fuel higher and enriched my actual AFR's while in turn, artificially leaned-out my AFRatioEst?

This theory seems to fit and it's easy enough to test. Yay again for a formula-driven GF adjustment spreadsheet that calculates the changes to the VE table cells. I'm going to dial my GF down to -51.6%, which gives me a max VE cell value of 100 (go figure) after everything is adjusted. I'll get that put in and we'll see what happens.

This is so much fun /ubbthreads/images/graemlins/smile.gif
 
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