Single channel O2

[Adger Smith]

Charles,
You hit the nail on the head with your last post.
It is just Data....not written in stone... I like to use the EGT cross reference along with reading plugs. As far as customers being able to read them you are right.. Some know a little about it some know a lot and some know a lot less than they think. Most of my customers/friends are told to learn as you go. Look at the plug and make a change you think is correct (that all other data suggests). Then after the tune up change look at the plug and see what changed. They should learn trends and what to expect. Like you said...Reading the plug Keeps the tune up honest..
Let's talk "Air" ...
Someone has mentioned DA, a lot. Well I'm not so sure all your faith should be put in DA. Doesn't everyone know you can get the same DA by having several totally different conditions? (Baro, Vapor Pressure, Humidity, Temps, ect..) It's when the conditions change that the engine goes from lean or rich or rich to lean. A good carb tuner knows he has a slight window that the carb will take care of when conditions change, a little, but not when they move a lot. I've always worked with mechanical FI that is Stupid. It only changes when you make the change or the pump is going away and you loose pressure, volume or both.....
This could be a good discussion..
OK What you guys say???
Beard, do you remember when we got bitten when we forgot to monitor the vapor pressure? :~)