Supermann68

okay well im hoping to get down to 13's, maybe even 12's. my stang engine hastn been raced and its a 90 with about 200, 000 km's on it.. so i am worried about it if i do too much to it. i was thinking ill get a cold air intake, new exaust, headers. and i was wondering how much hp that would put me up. or how much time difference. also what are some other bolt ons that could help me out. thanks.