well, after a lot of work, i'm finally getting this thing into range.
came to the conclusion that at "idle", (which is non-existent) no matter what pilot i'm running, it's not getting enough air unless i open the throttle, which then starts dumping in fuel from the needle feed.
Even with the needle in the hole all the way, I could get it to run that way, but it was a full bypass of the idle range and more than half of the pilot circuit (still had fuel coming up past the needle) and it just ran way too rich. it left me always dumping too much fuel for the amount of air at idle.
That situation left me with no alternative but to modify the carb.
Nothing like hacking on a brand new one!
The choices were to enlarge the air feed to and through the pilot circuit or to modify the throttle slide with a cutaway on the backside to feed air across the pilot circuit's feed hole.
Given that i knew how much i was lifting the slide to achieve idle, i went with choice B. (also cheaper to replace a slide than the whole casting if it didn't work)
Interestingly enough, the slide's backside had a depression matching the front cutout as if there was another application that used a slide with front and back cutouts. So i carefully dremel sanded out a match to the front (3.0 mm slide).
Installed, i get idle with the slide fully closed (idle screw all the way out) and the main feed not adding fuel. Drive test is still giving me a soot-ringed base and clean to grey porcelein. I think the pilot jet is a touch rich and the main is lean. needle is on center.
Pulls good and strong down low, gets soggy/stuttery up top.
Time for some more jet testing now.
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