Dyno tests prove it dynomax's super turbo mufflers are the closest you can get to running an open pipe but a lot quieter. To make things even better super turbos have more features than most other mufflers put together. Less backpressure for improved quarter mile times aluminized construction for long life and good looks patented flow directors that channel exhaust for maximum performance and fiberglass matting for a deep throaty powerful performance tone.