mike, i have a silencer but it only screws in on one side so it vibrates. the other thing is i hate the way a silencer looks in my exhaust. i also just bought a high flow cat that will be going in this weekend so we will see how much of a diff. it will make. i still might buy a muffler if i can find one that looks like the stock dual tip. my neighbor is a retired welder so he will do all my exhaust work for free.