In some cases the bigger ifrs/idle bleed combos help as you found out and lately I've been putting in bigger ifr's to help out the idle/transition circuits and to come up on the boosters happier instead of a big lean dip. However, this apply's to some and others may need to be leaner for various reasons but the wide band and plug reading go a long way here and a chassis dyno better yet........
When you add bigger ifrs, what does it do to the idle fuel screws; do you normally have to turn them in some more?
For me if the mixture screws have to be turned too far in say 1/2 turn from seated then I size down the ifr's and if they need to be like 2 turns out then bigger ifr's as a starting point. I size the idle bleeds according to the ifr's and go from there seeing/feeling the differences good and bad. I find the mixture screws play a HUGE role in how rich/lean the idle, transfer and cruise is on my Dart and there's a big difference between 1 3/4 turns out and 2 turns once it has heat in it. Same w/leaner mixtures, my car recovers faster when the happy peddle is mashed being in the 12-13 afr range while leaving a stop light and cruising instead of the 14-15's...........
