Depends what noise you're talking about. Normal engine noise is only a bit louder, particularly at WOT- but not really super noticeable unless you've heard the car with and without the stock airbox. The stuff that makes more noise is the IAC (idle air control) since the air is having to rush through a tiny tube around the throttle blade under pretty high vacuum (can sound a little like a vacuum cleaner, especially when its ice cold).

Not sure where you heard that, but you're not going to gain 10% fuel economy by doing a CAI box (ok I suppose its feasible if your stock filter was almost completely plugged)- but really you're going to gain very little in terms of fuel economy- modern airboxes really aren't usually that restrictive. Definitely not enough to warrant spending $300 on an intake setup and thinking its going to pay for itself (maybe if you owned the car until it died, you might recoup the cost).

If you're seriously worried about fuel economy, the high output alternator, and all the sound system equipment is probably going to hurt you as much or more than the CAI will help.

lol, I hope you're kidding

 

I havnt seen this thread yet?? I just wanna give my opinion here, the whole CAI deal, IMO, is worth every cent... If you make it yourself. I know some people here like to buy the kits from ZZP and such and thats great... Cause they have the money, but I dont so I always reccomend people to make their own CAI, thats what I did and I saved about 140 dollars over those high end kits that everyone here has. Its very easy even if you dont know what you're doing at first, all you have to do is a little research and make sure oyu dont have any leaks. My other opinion on this is, the sound is awesome, really makes people question what you got under the hood. Very good investment for both money, performance and pleasure.
Also, the HID's are somthing really cool to get: great GREAT light output, and you can get different colors to match your prefrence.

 

x2 with people wondering whats under the hood, i have random people asking me what kind of exhaust i have all the time, im just like, stock..., they usually dont believe me but i prefer to keep my secret haha

i would really recommend HID kits also, i have bad eyes at night so i needed glasses, which made my sight like 20x better at night, hid kit made my site about 10x better on top of that, i could see a ton further too.

 

Ah, just noticed the new sig... Need to add somthing to the list dont you?? Ahemm ubend delete??

 

fixed er for ya haha, and added upcomings.