Put a K&N filter in my stock air box, that I swiss cheesed. Anyone who owns a SOHC like mine, I recommend it for a cheap mod. Will probably go with a good intake and exhaust later, but for now, WOW!!!!Get on it hard and in the middle of the rpm band the engine is a lot more throaty as it sucks down that fresh air. Anxious to see what it does to my gas mileage, if I can keep my foot out of it.