I've been lurking at various sites including Innovates in an attempt to learn a little more about these AFR meters, particularly the LM-1. I was under the impression that 14.7 was the ideal mixture that was needed to obtain peak performance. That would be easy. However, I've learned that 12-13 is right for power, 12-14 is good for idle. And 14.7 is good for cruise. I've noticed some trends. One example that I see is when performance cars get close to 14.7, they sometimes stumble, so you have to jet back to rich. If you adjust mixture screws to 14.7, motor won't idle right or another stumble developes. For WOT, they say jet for MPH. The posts that I follow end-up with the AFR user basically having to jet to where their car runs right regardless of what the AFR is.

Question is, if I keep leaning out the carb till I feel a loss of performance, then correct it, why do I need a meter?

Thanks
Keith

i use one and it came in handy, when they dyno'd my car it ran best when rich showing on their wide band and my little autometer 02 sensor, you can see differences just when the temp outside changes... after a while i go to where i look constantly at it and use it as much as my oil/temp guages...plus my motor is a bit radical and hard to tune sometimes... the guage really works to tell ya when you'r going lean in part-throttle light throttle applications... i like mine :)