Review on 🚗 K&N Cold Air Intake Kit: Boost Horsepower, Enhance Performance: 50-State Legal: Fits 2005-2010 MAZDA (MX-5 III)57A-6023 by Troy Drake

If you install it according to the instructions (and it's pathetic), then use the large black hose in the picture. You may find that the diameter of the hose is no larger than the diameter of the fluid inlet. If you run a hose it sounds and drives about the same as the stock and looks a little goofy under the hood. Omitting the hose is no longer a "cold air intake", although you're primarily drawing in cold air through an opening at the front of the engine compartment. louder (in a good way). Maybe not faster, but it definitely makes me want to go faster just to hear him howl. Pretty expensive for usable parts.