K&N Filter or CAI??

I installed a Green Filter (similar to K&N). I clean it every 15K and oil it lightly. It works great. No issues.

A fellow stangnet member dynoed his car w/ a K&N drop in and with the stock paper filter. No gain. A CAI will flow better with the increased tube diameter and larger MAF to allow more air to enter. If you do go with a CAI, a tune is strongly recommended. The stock MAF only allows so much air. With a CAI/no tune, you might throw a CEL or get some pinging at higher RPM. As for the oil contaminating the MAF, just don't oil it from the inside and it shouldn't clog the MAF. I may be alone on this but if the cotton high flow filters are superior, why aren't they OEM equipment? I guess the average stang owner might somehow mess up the cleaning/re-oiling process. GT500 and bullits have a paper open element, must be a reason.

A lot of issues with oiled filters occur because people over oil them. I've used K&N for over 10 years now in all my cars, I wash them, re-oil them, and never have any problems. Saying that, the green filter mentioned is also a great filter.

If you shop for a CAI, which I'd recommend, find one that has a tuner specifically made for it and you will be fine. Don't settle for one without a retune. A steeda package is a no guess approach and is what I'm eventually going to do.