On the 5.0, which uses the same filter as us, the K&N panel filter was worth negative 3 ft. lbs. of torque. I titled my thread wrong by saying "HP", should've said "Tq". So if you are looking for more torque get a CAI and a Tune. I have over 40K on my 2011 with extended warranty to 70K, no warranty problems here. https://www.allfordmustangs.com/forum...tive-3-hp.html
BTW, I've used many K&N filters and still have one on the old truck, and they used to help power a little, but not anymore.