every ion is different. do u have an aftermarket bolt? this is posted everywhere but ill still help you. my ion did a good dwell at 16. but that doesnt mean yours will. start from the bottom and slowly go up until it starts cycling. then go up a few over that. that should set u a good dwell. start at 10 and then slowly go up. if it barely does anything jump up about 4 then try that. then go up 1 and so forth.