Yes, it produces AT LEAST 15rwhp - I really questioned that claim as NO OTHER MUFFLER or even cat back system offers anywhere near that performance for the price. I’ll split the Dyno charges with anyone who wants to do a before/after run comparison. I got one and dynoed BEFORE and AFTER and saw more like 17 rwhp. The mufflers are finally shipping next week. Cat backs are another $225+ which gets you another horse or 2 and allows you to bolt it on instead of paying $40 to have a muffler shop do it. But John needs 10 orders to make the cat backs.