the relationship between the idle jet (tube in the well) and the idle air bleed are screwed up on those mopar holleys. I always do the idle jet half the diameter of the air bleed, the old way was to just reduce the air bleed size. this was done by tamping a piece of #4 lead shot into the air bleed hole and drilling the lead. in this case the air bleed would end up at .044". I've done this before but really believe you need to go after this in both directions. reducing the air bleed gives a stronger signal to the idle circuit but those small jets will only flow so much fuel. the last one I did for a six pak I drilled out the idle jet to .028" (was .0023") and reduced the air bleed to .056" with the lead shot. those brass tubes won't allow a proper diameter jet but area wise small changes can make big differences in area. the hard part is going thru the bottom of the metering block to get to the idle jet and deciding how to plug the hole up. I used 6-32 set screws thinking I may want to get back in there to clean a jet up. I was afraid of removing the idle jet from the metering block and damaging them and not being able replace them. quick fuel makes a universal metering block that might be easier if nhra tech allows it.
