Check out this article.

http://www.royalpurple.com/tpr1/tpr1p1.html


A little bit might be gained, but especially on an auto, it might not be terribly noticable. I've opted to do pretty much nothing above a K&N filter for this reason. And the main reason I even did the K&N was because I was sick of wasting money on $12 air filters, not so much for performance since again, it is minimal. Stock you'll get around 150hp max, with those mods, yeah, I'd +1 the 160.