:blowtiedb:I would like to have a discussion on exhaust systems what makes them sound the way they do. I have had some good experinces with my 55 chevy. I am working on another car with a chevy motor in it. I used 2 1/2 inch pipe on the car with flowmaster super 44's on it At idle the car sounds fantastic. However at 40-50 miles an hour there is a drone inside the car. I know there is something we can do to eliminate this. It might be a bend or something. I would like to see if we can identify what makes this happen so we can eliminate it. The size of pipe, size of muffler, short headers verse full headers.