I got the stock K&N replacement filter.This seemed to make a good difference without the top snorkel or restrictor.Then I cut the bottom out of the air box and filter.This helped also,of course with rejetting.You can hear the difference when you first do it and feel it ,if you rejet.To me that is.I currently am considering doing away with the air box and going with the seperate filters.They all seem to think it makes a big difference that have done it.
