Better gas milage?... ANYONE?

[Verocithrax]

Ok, so I haven't posted all that much in here, kinda a newbie, but regardless, I just wanted some other opinions on this topic...

Does anyone know how to obtain better gas milage with a 98 aurora? I did a little test for myself and realized that you can use the cruise control when on highways (no kidding), and if you keep it on cruise at @ 62 mph, I'll get roughly 26-28 mpg, but if I dont, I only get about 18 mpg. HERE is where the question begins... I'm a big on "believe it when I see it", but does the concept of an Air Intake actually improve gas milage or is it more or less just for power? Also, anyone that has one in their car, does it REALLY make that much of a difference in sound because I personally like the fact that my car is relatively silent. Thanks in advance!