Will I need a tune?
 

I have a 2011 G37XS sedan, I am planning on getting a K&N Typhoon or Blackhawk kit as well as a axle back exhaust. Will I need a tune for the car for it to run decently, or should I be okay with just resetting the ECU. PS I'm Canadian so from what I can see we don't have any up rev tuners close by.

With such little performance mods you will be fine with a tune the car should run pretty much oem with those bolt ons...

K&N typhoon will make you lose power and the axle back wont help you get any.
You also dont need tuners nearby - just get a e-tune/

Why would the cold air intake make me lose power and i am guessing a catback is the way to go?

Because its not a cold air intake.... it sits right in the hot engine bay sucking in hot air. Personally I think drop-in filters will get you 95% the effect of any CAI on the market (I'm sure many will challenge me on this)
Catback is the way to go yeah, but depends on your goals and budget.

Oh okay i thought the heat shields helped for the k and n. I am currently a student making around $1200 a month and half of that goes to gas and insurance alone. So i am able to get quality parts it will just take me some time :(

Yeah fair enough, but you have to be realistic with your goals. No mods (except FI) will get you any major gains.

Also "buy once, cry once". Just save up and buy quality parts. The car is fun enough stock.

Yea i've seen enough of my friends buy junk parts to learn that lesson. I was looking into Invidia cat back and possibly an intake if I can find a good one. Thanks for the help man I appreciate it.