If i in the future do turbo my 5sfe, would it be a smart choice not to touch the engine bay stuff and exhuast?
Cause i was reading on the forum if you have turbo it would be a wiser choice to go with 3" piping all the way down, while if a normal 5sfe it would be better to use like 2 1/4 inch piping. And i was thinking to get a CAI + pod filter, and that would probably need to get changed after the turbo right?

Cause it would really be stupid spending all that money when in the future i would need to change it again

Well you can still get the CAI and the exhaust. I wouldn't lose to much sleep over 2.5 or 3" piping. True, there are more gains to be had with 3" piping, but nothing that will break the bank. 2.5" exhaust is good till 400hp. You can also install the 2.5" exhaust now, and when you turbo your car......if you feel you want a better flowing exhaust than the 2.5" can give you, you can install an exhaust cutout after your 3" downpipe. As for the CAI, you will be able to modify it to fit your future turbo setup. So no, items such as exhaust and intake are NOT a waste of money.