I'm tuning a '02 Corvette and ran into something new. I noticed during some WOT 'runs' that the commanded a/f would suddendly drop from the 12.5 I had set to arond 11.9, and the reading on my WB reflected this change. I later cooralated this occuring at the same moment of knock retard. I didn't realize that additional fuel enrichment occured during knock retard, and I can not find a way of editing this. Is this an editable parameter with HP tuners??
Last edited by vetteman3; 06-10-2008 at 02:42 PM.
anybody??
Are you sure it wasn't COT?
Bill Winters
Former owner/builder/tuner of the FarmVette
Out of the LSx tuning game
Could be as it is a common issueOriginally Posted by 5_Liter_Eater
COT was my first thought also, so I disabled it, and no difference!!
Any other ideas?
There are some tables that link spark advance and
AFR commanded, I haven't played with but remember
seeing them. Wonder if there is a bump happening
through this linkage.
If you had an "air surge" that might push open loop
EQ up and you'd hope spark down, but if it's in a
range where you never adjusted the advance table
then maybe the fuel & spark are just not what the
air charge likes, and fuel alone isn't covering it?
I have heard anecdotes about overfueling giving
unexpected KR (or failing to cover timing?). I'd say
you want to understand the fuel bump first.
Without posting the tune & scanner log its a guessing game which I don't like to play.
It doesn't have to be perfect, it just needs to be done in two weeks...
A wise man once said "google it"
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