Bought a uni foam filter and installed on throttle body. Removed 2 10 mm bolts and removed airbox.put sensor just in front of filter with a ziptie. Sounds awsome and revs way better. Havnt ridden it yet its 19 and snowstorm. Cant wait for spring. Its made the yosh pipe sound better too. You can hear the chug of throttle body but i like it. These little street murder machines are so fun!!