Dude, CAI won't get you much gain, if any at all... only because I've done it on my car itself. I have some flex pipe going from the bottom bar, to the airbox, with a K&N Panel Filter, yet it doesn't make any difference... nothing noticeable anyway. I know lots of lads that have done this with their Camrys... the only advantages are: not having to replace the filter again & the "sucking" noise that you get when you plant ya foot mate! If you're looking for smoothness, treat the car well, service the car and add some engine treatment to the engine oil (done at the same time as the service) and run 98 octane for a few tanks with a total system cleaner from Nulon. A set of Hurricane or Wildcat extractors wouldn't hurt... and maybe an upgraded exhaust, but that's the most gain you'll get, unless you do port and polish (best bang for your buck)... looking around 700-1k bucks, but may add an extra 20 or so kw on average. The other way... custom supercharger or turbo :) I seen both :P Looks awesome.