This is the response I got:

This material (and all MegaSquirt materials) is copyrighted. However, you can copy the glossary if you retain the original copyright notice "©2006 Bruce Bowling and Al Grippo. All rights reserved." and include a prominent link to the original web page.

That sounds extemely generous, and more than fair. Maybe just a link would be enough. Convenience can sometimes be outwieghed by the volume of information that would show up here. Maybe a good link is fine. We are still in the begining stages of trying to put something usefull together here, and a list of useful web sites would certainly fall into place somewhere I would think. I have never done anything like this before, so any ideas or suggestions can only help, and will contribute to the shape things take. If youlook on the Corvetteforum that I used to belong to, you will see that there are 5 or 6 stickies that hang at the top of the list of threads, and that get added to, and or edited from time to time. EAch one deals with a specific topic that has sort of continual interest. AT least one of them is forum etiquette. I know we have that somewhere else here, but maybe techincal threads that seem to be very basic in nature could be kept at the top. Just thinking out loud here.
Sam

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Very true - I've committed a similar version of the same mistake. Tried to tune the VE table when my engine was cold because it seemed to be running too lean. And when it warmed up, the engine went way rich.

It may be all right to temporarily plug in warm-up enrichment numbers to get the engine warmed up. But it's never a good idea to play with the VE table on a cold engine, and it definitely seems like a good principle to get the VE table all dialed in first on a warmed up engine.
Interesting - that seems to be a bit different with Accel's software. On MegaTune, it's possible to monitor how much the ECU is compensating for the O2 sensor and use that to tune, so it's possible to run closed loop right out of the box.
Preach it, brother Sam! I've had to do a restore from backup a couple times too.

I'll post two of my own big lessons, both about MegaTune's automatic tuning, but they may apply to other software as well.

1. If you are at a point in the VE table on the edge of where AutoTune is allowed to tune - if it's disabled below a certain RPM or above a certain MAP value - it will overcompensate on the edge areas if you haven't tuned it manually. So you end up with values where it runs way too rich on the edge of where AutoTune is active unless you fix the adjacent points.

2. Never turn on AutoTune when driving around in heavy traffic. It accidentally made a few changes that made it impossible for my Dart to go over 25 mph, and I had to pull into a parking lot to retune it!

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

Matt - I had autotune set in stop and go commute w/o problems. If the original map it started with was way off that can happen... or if the o2 sensor is falsly reading or gets stuck - that happend once to me, my o2 sensor was on the fritz, it pegged rich, autotune made one point significantly lean and engine started surging.

What did it do that you couldn't drive over 25mph? Made one point excessively rich?

Actually, it made two points in a series excessively rich, both on the edges of where it was allowed to tune. I'd just started with a way-off autogenerated base map.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair

A point worth mentioning here is that when the actual operating point of an engine is near the edge of the cell, it does an averaging calculation between the two cells. So if they are way different, the neighbor can pull it way off track. I think that is what was happening there.

That business of having the O2 sensor fritzing out is a serious concern. They really seem to just get a wild hair every now and then. Are there any brands that are more reliable, or less reliable in the experience of members?

I am posting a response/question in the AF thread that is related to this topic.

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G'day Sam, FWIW I think this stick thread idea is great, keep it up.

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Richard (aka Fingers)

Well, I visited an EFI 101 class this weekend. While it was a beginning class and probably aimed at an audience less familiar with the mechanics of EFI, I did pick up a few interesting tuning principles.

Some were things we'd already concluded, such as the importance of getting the base fuel map correct on a completely warmed up engine before tuning the enrichments.

There were a couple other interesting principles I picked up there, too. Here are some that I think are going to be the most useful ones here:

1. An engine can make the same power on a surprisingly wide range of air-fuel ratios at low cylinder pressures. There's still a bit of tolerance under boost.

2. Often, you will want to pick your air-fuel ratios at high cylinder pressures to stave off detonation, not to make maximum power. Many (but not all) factory ECUs take this to cautious extremes; he mentioned that a stock Chevy LS1 often runs 9:1 at WOT for this reason. That's just barely lean enough to avoid having unburnt fuel get into the oil.

3. Tune the complete fuel map first with a conservative spark map, then adjust the spark. There's a considerable amount of power gain you can find with spark timing, but this extremely difficult to do except on a brake-type dyno capable of holding the engine at a constant RPM.

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"Mad Scientist" Matt Cramer
'66 Dart - turbocharged 225
My blog - Mad Scientist Matt's Lair