Drilling out idle jet

[crabandy]

I've searched the forums about drilling the main jet of the carb to properly richen the mixture. I'm hoping to do my first flight later this week and anticipate having to drill the main jet, more analysis after I'm flying.
I'm curious if anyone has also had to drill out the idle jet. I'm on my second carb, a rebuilt MA4-5 part #10-3878 for my o-360-A1F6D variant with dual electronic ignition. I believe the stock setting for the air screw is 1 1/4 turns out from lightly seated. The engine wants to cutout while slowly advancing the throttle from 600-900 rpm with the idle screw less than 2 turns out. 3-6 turns out the engine appears to run great, but no RPM increase on idle cut off. Accelerator pump working well, faster throttle changes work well.
I even used the air screw from my old carb which is visibly different with no change in the idle circuit.

I'm guessing after the air screw makes several turns out it isn't very effective and the idle jet needs to be larger.
Ideas??
Thanks,
Andy

[664781]

Look a for a air lerak, you are running lean. I have my 0-360 A1A at about 4.5 turns out. Had a similar problem with my old carb.