starting with the costs, basically, you will only pay for what you get. Air filters and air intake systems are the €asy part. Most of the work you can diy. If you're thinking about a remap, then start to think about higher figur€s and something that it can't be done by yourself.
There are a few places where you can have it done in Portugal and if you want to know more about that I can dig the info for you. But don't expect it to be cheap. Besides, I have some doubts about their work...
An air intake kit migh improve the high end power availability but it wont be really significant (don't go by their numbers!) On the other hand, you'll have more noise coming from the intake. Some people like it some don't. You wont need to change the filter anymore (just do the correct cleaning) so it might become cheap on a long run.
Did you posted some shots before? Sorry, can't remember where...
(2011) Alfa Romeo Giulietta 1.6JTDm, Pack Sport 17", Pack Comfort
(2009) Alfa Romeo 159 1.9JTDm 16V QV, 170hp+360nm, Bilstein B4+TI springs, ConnectNav G2, Autodelta Air filter, Brembo Disks, Satin Mirror Caps
(2002/2009) Alfa Romeo 147, 1.6TS QV, Autodelta Remap, Autodelta Air filter, Eibach Pro System Kit
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