How to properly drill carb jets?

MopaR&D said
Seems like the rich off-idle cruise is just the way these carbs work, lots of people complain about that online. However it always seems to be "I don't like the numbers my AFR gauge is showing but it runs fantastic" so I'm just gonna roll with it.

You're using your noodle. :) Tuning for performance is right. Shooting for a number on a meter only works if every assumption involved is correct. And the fact WBO2 AFR numbers are themselves interpretations dependent on assumptions about the combustion doesn't help. You're right. They're reference tool, not a targeting tool.

MopaR&D said
Even the owner's manual that comes with the carb says to target a 13.5:1 mixture at cruise using a wideband, seems pretty rich but that's what they say. I have a feeling it's designed to have a lot of "crossover" between the idle and primary circuits to give that excellent response.

Or maybe whomever put together the manual didn't really know their stuff.
Like this graphic that shows up in several of the Eddy instructions.

It's just plain wrong.
Mislead many of us for many a years.
Part throttle acceleration actually should go leaner than cruise at pretty much all speeds.

Go back to the text books based on testing and experimentation for the automotive and aircraft industries.
A little synopsis from Larew's here:
https://www.forabodiesonly.com/mopa...g-to-compare-to.395945/page-3#post-1971911709

More here:
https://www.tapatalk.com/groups/rac...r-characteristics-at-differen-t421.html#p3408

Some links to various papers (getting much more technical):
https://www.tapatalk.com/groups/racingfuelsystems/metering-characteristics-of-carburetors-t14.html
https://www.tapatalk.com/groups/racingfuelsystems/air-bleed-characteristics-t80.html

Carter type calibrations discussed here, including the "economizer" and "bypass air bleed"
https://www.tapatalk.com/groups/rac...ry-of-the-carter-idle-restricions--t2055.html