Holley stumble trouble

Read the discussion I linked to. Especially the discussion between Deep Roots and Tuner toward the end. This seems to be one of those situations where sometimes the kill bleed in the dogleg is just enough to really kill the start of the boosters and sometimes its not a problem at all.
When I get my car running, I'll be curious to see how well my 650 carb does with those dogleg holes now plugged.

I agree the IAB in particular seems very small. Maybe that's the secondary block??
Deeproots and Gntkllr posted a fair number of that should be good guidance for getting this into the ballpark. IIRC numbers are all in the same range as you (Mderoy) suggest.
Also in the same range as my 650 VS. I don't have 600 or 650 DP or I'd post that too.
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So primary IFR is just over .033" and IAB is .073"
I decided to drill regular kill bleeds in both blocks. I'm not sure if the ones in the primary block will help or hurt. On secondary block that was specifically done as a siphon break.
The reason I've reduced the primary high speed air bleeds was because the AFR on the dyno was showing increasing need for correction corresponding to the reduction in jet sizes. Only when I take it to the track with a working logger will I know whether this was a move in the right direction, and if it was, whether it was sufficient, too much or too little.
2x.027 and .026 or .028 MAB has always given me a flat fuel curve with a fuel delivery system that can feed the motor.