I own a Cyberdyne air/fuel gauge that I bought from Jeg's a million years ago. It's old and still sold @Summit for $99.
But it's not like the one
@rich weyand touts. There are no numbers to read or fanciness like they got nowdays!
It's an LCD? bar graph kind of thing that is green or red - rich to lean.
I used it for tuning the jets, accelerator pump, and idle after determining I was going lean at the big end. Can also be used with ignition timing to an extent.
The car USED to see a lot of hot street racing action back in the day and idle quality was actually an issue long since passed.
Not very "scientific" at all. Change something - go run it a couple of times to watch the gauge and change it again if need be to try and keep it in the green at different times or at varying distances. lol. Exactly how much yellow was reasonable at where? Give and take. It's for a different type of tuning than you may be after - or maybe it's EXACTLY what you need?
The only number I was after was 12.5......seconds, haha.
What I have is an excellent tuning tool for ME and my purpose-built bracket race car. It is a very "hands on" device that I used for turning wrenches. - Lots!
Plus it's easy to look at when you're driving way too fast.
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