Holley/Demon Carb stumble

https://www.summitracing.com/parts/pro-67245
https://www.summitracing.com/parts/pro-67246

These are the kits I have. I usually go 2 sizes at a time to see any difference. The inner bleeds are the high speed bleeds and the outers are the idle bleeds. I'd start with 28 HS and 73 ID. I think that main body comes with 33/73 bleeds.
I you have the idle screw out so far that the idle mix screws make no difference you need to drill the throttle plates an back the idle speed screw down until the transfer slots look like squares. The smaller ID bleed will make the idle richer.



Been so long since I've seen anything BG I can't remember if those metering blocks have adjustable emulsion, idle feed restriction and power valve channels?

You can always make them adjustable, I just don't remember what they came with.