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[snm95ls]

Alright niggles.  I am trying to get my fuel trims nailed down since the temps have plemeted.  Between juggling post fuel trim, VE enrichment tables, IAT and ECT trims, it is becoming a bit of a fiasco.  It could be mostly that I don't have a lot of time to dedicate to it.  When I always ran the free version of Crome, I could get cold start and warm up fuel nailed in a pretty short amount of time.  With Neptune, it seems to be more of a chore for some reason.

With the default IAT and ECT trims, A/F during warm up is way too rich.  I was as bad as low 10s at one point.

I used stoich as my center point for ECT trim at about 195 degrees F and used desired A/F for each temperature set point from there based on the proportion to stoich.

After doing this, I am running very lean during warm up, like 16-17.

For IAT, I was going to use ideal gas law, somewhat flawed for this methinks, as a baseline for IAT trims.  The trim values I come up with by doing this are quite a bit different form what the default settings are.  Yes, I used the absolute temperature scale, Rankine, to calculate the trims.

Am I off my rocker here?  This should be easier no?

Advice, criticism, lewd comments?

[Joseph Davis]

Tune car once at operating temperature.  Allow to cool overnight, set warm up (ECT) enrich in the morning - 12s for the bitter cold to 13s to stoich at full operating temp.  When seasons change fire back up the laptop and tweak IAT trims until things fall back in line.

I never use VE, always disable it.  Whether disabled or not its not anything you ever fuck with after the initial tune.

[snm95ls]

Tune car once at operating temperature.  Allow to cool overnight, set warm up (ECT) enrich in the morning - 12s for the bitter cold to 13s to stoich at full operating temp.  When seasons change fire back up the laptop and tweak IAT trims until things fall back in line.

I never use VE, always disable it.  Whether disabled or not its not anything you ever fuck with after the initial tune.

I am thinking about redoing the fuel map.  The VE table seems like more a nuisance than anything else.  I can sort of understand the logic behind it, but I don;'t understand why it is only active for open loop after 126 degree ECT.

That is pretty much how I have always done it before with Crome.  I think the time issue is the main culprit here.

[Joseph Davis]

Make time.