carb question,please help
 

i have an 85 2.8 v6 carbd motor,the car its in is used for enduro racing so its gutted of ALL unessary things.my question is, what controls the fuel mixture? the "brain box"? does it use the o2 sensor for signals to increase or decrease fuel? can i remove the 02 sensor? could i remove the brain box and wire the car on a push button? its running too rich,fouling the plugs too easy. if i adjust the timing or the carb will the brain box re set to other settings? or how could i just lean it out? if you want to send a reply to my e mail thats fine. thanks for the help!! knightl35@yahoo.com