Just bought an 08 4 door with the 2.0. does anyone know about any do it yourself mods for the stock intake box aside from replacing the stock filter with a K&N or the like?

 

what kind of mods are you looking for? the stock air box lets the right amount of air in. Unless you get a different filter or a cold air intake. i dont think there's much you can mod on the air box

 

I built my own CAI only cost about $50 bucks its 3" all the way to the filter, works for me.

 

I have a K&N filter if you want to buy one - I had it in for a couple tank fulls and saw no difference from stock, so I pulled it back out.
I did pull the front bumper and add a hole in part of the duct work, to allow more of a ram air situation. but haven't looked at my stats to see if it improved mileage on the highway - though it has nosignificant impact on mileage during normal driving. no impact on 0-60 that I measured either.