This is the air filter we use for all of our 5" inlet turbos. It flows very well for its compact size and we've made over 1000hp without issue. The main issue with air filters is as your engine/turbo setup demands more air flow you don't always have the room. This filter is the best compromise we've found between high flow, small size, and efficient air filtration. This filter has a 5" inlet flange, a 9" x 7-1/2" Oval Base, a 6-3/4" x 5-1/2" Oval top, and is 6-7/8" tall with a 2 1/2" x 3 1/2" reverse cone in the top.
