As for my 3.0 L, Ive got a 2 1/2 inch pipe runnin from the catalytic converter, it runs into a (single 2 1/2 inch inlet / dual 2 1/4 inch outlets) Flowmaster Super 44 series muffler, with 2 1/4 inch pipes comin straight out the back of the muffler, all of which runs into 3 inch chrome tips. As for the sound, in my opinion, it sounds pretty good, It resonates a deep growl at idle, and when drivin around the hood, and offroad, it sounds pretty good for a little V6 engine. The only problem i have is when I get on the highway, the loudness becomes a drone and it can be a bit annoying, but ive gotten used to it, besides, thats what u use ur radio for, the drown out the drone of your vehicle.