Sure it does, that represents a significant power increase. But remember you also get more linear throttle response from a muffled engine and no setup issues. So if you have all the power you need or want with a muffler, then stick with it. But if you want to try out a tuned pipe setup, then go for it. The Jettstream mufflers are a nice compromise, not as much power boost as a full pipe, and less hassle.