There's many choices when it comes to an intake replacement doing a stage 1. Here are a few choices to help you out there. I have furnished the links for the stage 1 mostly from the manufacturers but shopping around can get you a better price on a lot of them. Big Sucker by Arlen Ness Arlen Ness - Big Sucker Doherty Power Pac Power PACCDoherty Machine Harley Davidson stage 1 kits for different models A Virginia Harley Dealer, Waugh Enterprises Harley-Davidson K&N Engineering K&N Custom Air Cleaners & Replacement Air Filters for Harley Davidson Motorcycles Zippers Taller Filter element for 320CFM Product List MORE TO COME.