removing the lead plugs at the bottom of the carb will expose the mixture screws. these are for gas mixture. the top left hand thread screw is for air only. it's kinda like an adjustable air bleed. the bottom mixture screws can noticeably improve idle quality. removing the top of the carb and taking out the two clusters will expose the emulsion tubes and idle jet (the small brass tube). enlarging the idle jet orifice, especially on automatic trans cars, along with working mixture screws can make a big improvement in idle and low speed engine operation.
This is timely and helpful for me too, as I've been unhappy with idle performance on one of mine. When you talk about the idle jet, you mean just drilling out the end of the small tube? Recommendation on how much enlargement is needed? Thanks in advance!
