holley carb help,transition/stage

A smaller IAB will richen the upper rpm portion of the idle circuit ie 2000rpm. Your car cleans up at 2500 due to the primary being all the way in. Put .067 IABs in at least the front and readjust idle mixture for best idle. On a race car I set idle mixture to the fat side since you really don't idle much and the motor is run much colder than a street car.
The IAB controls the air allowed in the idle well, the IFR the amount of fuel, the idle mixture screw controls how much of the idle air/fuel mixture goes to the idle and transition slot.


This is kinda what I had in mind, drop the iab down, your thinking that much from apprx .072 to .067, of course idk is that even alot for iab. Will this change anything timing wise with the mains coming in? or just swap those iab in front only and retrim the idle mix screws. No issue with having different iabs front to rear?