2005 kia rio areo tuning?
 

looking to try to tune my kia rio to save fuel, but i have no clue were to start.

I'll start it off:

Inflate your tyres - some people run up to 50psi (3.5bar)
Clear out all unneccesary junk from the car to make it lighter (some even remove the spare wheel)
Fit tyres with larger diameter than stock (makes every gear longer)
Choose tyres with low rolling resistance

so my sub system bad. lol sorry i love sound

any good ideas how to reduce weight without taking out ac or the interior looking like i stripped it out

It depends how far you want to go. How about rear headrests they're worth a couple of kilos? Ditch the spare wheel and strip out the boot lining?

Take a look underneath the car and see if you've got flat plastic panels or lots of components on display. Anything smooth is good for airflow and less drag - including blocking off grilles on the front of the car.

Everything is compromise - you can keep your sub but it'll cost you fuel to carry it around hehe

yeah i know but once you got one its hard to get rid of it because it sound dull after its gone

also do body kits increase or decrease im seeing different answers everywhere

Most bodykits will create downforce, or have aggressive edges for styling purposes. For good aerodynamics you want silky smooth and minimal aerodynamic effects like downforce or lift. Take this airdam for example, it will improve MPG:
65+ Vehicle modifications for better fuel economy - EcoModder.com

k thanks

anything interior wise worth removing?