First thing for power would be a Cobb AccessPort. I'd get it from MAPerformance and use their stage 1 tune. Their tune is really solid and I never had a problem After that the next big power adder is a j-pipe. You can add an intake but that's mostly for cool sounds. I'd recommend not using OTS tunes with any parts installed, but there are stage 2 OTS tunes if you install a j-pipe. Some people have no problems with that.