Pics from today. Adjusting idle mixture is not a problem. Good precise control on all 4 corners. Actually leaned it out a bit ( about 1/8 turn on all 4 screws ) and I am attributing that to a better looking plug - from the previous pics. As an FYI, the carb is a "Pro-Systems" carb - originally a 950 set up for my NA motor. When I went to my existing blower motor, I gave it back to them for the blow through modifications. Carb came back with lots of changes ( jets, boosters, PV feed channel, Hi air, Idle air, idle feed, Sec pump size, etc ). I did drop some jet sizes with todays test, ( still 3 sizes larger than what the carb came with ), but think I'm pissing in the wind on jetting until I can get some MPH numbers at the track. BTW, with the plugs you are looking at have had several cleanings and some street testing on them and with todays test, the motor started to go away over 6K. Gonna drop the right side header today and weld in a bung for my W/B.