Air:Fuel Help. Cannot Get it Rich

mbaird said

I may have missed this but how do you know its running lean ? A/F gauge ? Checking plugs ? Is it popping ?

Could be bad sensor or gauge...

I once chased a lean issue and found it to be a kinked line at the tank. Must have done it while changing gears.

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1/4 mile ET and MPH fell off about 3 tenths and 3-4mph, checked plugs and all of them went from rich to white lean. It's open headers at the track and I do believe I've heard popping once (while doing burnout at higher RPM). It hasn't just "layed-over" while making a pass, but you can feel a difference.
I do have an o2 gauge and new sending unit, but I do not trust the reading. It's telling me 10.5:1 at the top end of the track, and that's just not possible with how the plugs look. It's a new sending unit as my first one stopped sending a signal (because I think i was running rich for so long), so i'm not sure why it's giving me such a rich reading.