Welcome to the club! Great first mod choice. Too many people talk about getting blow off valves and cold air intakes as their first mods. I am running the Cobb 2.5 map and I love it. I also have friends that run other maps and love them too! As for other undetectable mods you might be able to pull off a TurboXS stealthback exhaust and keep the rear muffler. The exhaust sounds basically stock except for some turbo noise. Then you could run the Cobb stage 2 map.