I am looking for a cat back system, or more importantly, just mufflers, that will not give me highway drone. I have BBK longtube headers, and a BBK catted H-Pipe. I have tried dynomax super turbos, flowmaster 50 series, and the forty series, (came with the car). Each one sounds great when revving, but will drive you crazy at 55-70 miles per hour. I know I have built a muscle car, but I have put way too much money into this car to have it sound like a truck, or a stock stang with a loud exhaust. Anyone know of any other mufflers that could give me a quality sound, without the drone? I would even consider something close to stock sound, with good flow. Any suggestions would be very appreciated.