Might as well give this a shot!

My car nissan 240sx hatchback I need a way to get it tuned without fouling the plugs every few hours.
setup is aem fic,550cc,t28/t3 hybrid, walbro, damn car has no obd port because of the wiring harness I had to use to replace the old shitty one. I have a wide band car sits at about 12:1 at idle on average with all stock settings. When I try and lean it out it skips on accel no smooth transition, and jumps to 18:1 wtf