I am currently running long tube headers and thats it. I would like to make the car a bit quieter. I was thinking about plumbing the 83 mustangs exhaust to come out just IN FRONT of the rear tires. I am just going to use 3" pipe to get there. Id like to know if anyone has ever tried fiberglass pack muffler or I was looking at some turndowns with a cone baffle in them. The turndowns dont look too restrictive but will they quiet it down at all?

 

you will lose power with 3 inch exhaust. go with slp exhaust. Its a chamberless muffler system, kind of like a glass pack, but a hell of a lot better.