I've seen the same problem with at lot of engines, mainly after 3 to 4 mins run time, in those cases the Bottom needle is too lean. especially if the car runs good for the first 2 or 3 mins. Does your car do this? (runs ok for a few mins). If so before you adjust anything else richen bottom jet 1/2 turn,if that's good or worse go another 1/4 either way. then work from there. Once you get it close then start adjustly Bottom and main, 1/8 turns together to fine tune it. Hope this helps. Works with all my
modded engines.
People sometimes over look a lean condition at bottom due to a few things and your setting are really just misjudged. The setting you have and to much or less idle opening can really mess with the bottom performance seems too me this area is kinda overlooked sometimes. Just a thought! BB.