Sorry i have not been on for awhile, screwing with this weber triing to tune it. Here is the senerio. Fallon sits at 3900 and some change in ft. above sea level. Conventional weber tuning says i should be running about a 40-50 primary idle jet. To achieve best lean idle i should only be 1 to 2 turns out on idle mix screw. Here is the problem in order for me to achieve this, ( I HAVE NO IDLE JETS ) on either side and mix screw is about 1 1/4 to 1 1/2 turns out, my timing is just about dead on at 10 degree BTDC. Does air correctors have anything to do with this i read that the air correctors do not come into play until about 4000 rpm or is this incorrect. i have the haynes weber book can not find any info about my problem. So i welcome all unconventional rational or whatever suggestions my help me with this thanks guys.