Well the tornado isn't very restrictive @ all..
what it does it causes the air to spin so when the fuel is added to it the fuel is spun into it causing a better more even mixture of air/fuel..
Which will make a more efficient burn make less fuel used for air..
as for the air intake.. What does it do? It give you more power.. What is the source of power? More air/fuel.. What does more air/fuel do to gas mileage? Makes it worse because your getting more power.. I would lighten up on the pedal if you want better fuel mileage.. MAke sure it is up to date with the maintance.. spark plugs/wires/ fuel filter.. good clean air filter.. (maybe a k&n drop in)
Keep the engine running efficient and smooth so it isn't wasting fuel..
less weight also if it isn't needed..
well a little update, blew through a 3/4 tank of gas all last night of straight driving, and i got 600, didnt push it at all(well much lol) so im thinking my mileage just went up because of a CAI or i got lucky, still havent changed my oil or plugs gonna do that tomorrow