ok i just put a k&n intake on my car. Are there any pro's or con's to leaving the duct that goes across the fan on or taking it off?

 

You're likely going to want to build a CAI box around the filter with heatproofing stuff on it to keep the warm air in the engine bay, and cold air going to the filter. When you do that, yank the stock air flow duct. It frees up a surprising amount of room.

 

alright thanks