The lip in the stock lid will not work for a K&N, plus, it looks pretty weak. I have alba's setup with K&N, max flow intake adapter, and outerwears and love it. I run with the lid and snorkel on and yes, it does make a difference that way. It's just not huge. If you plan on running with the lid off, you'll need to rejet, but between that and the new filter, you will definitely feel the increase. And if you plan on either gutting your current exaust, or buying a new one, the K&N really helps get the air in fast, so that the new exaust can let it out fast.