Super Turbo™ Aluminized Steel Oval Gray Exhaust Muffler (17664) by DynoMax®. Muffler Inlet Diameter: 2.25". Muffler Outlet Diameter: 2.5". Muffler Body Length: 18". Muffler Overall Length: 22.75". Muffler Sound: Mild / Stock. Muffler Structure: Turbo. Muffler Configuration: Center - Offset. Get improved exhaust flow and reduced back pressure for better performance, and a mellow tone without annoying interior resonance, with this Super Turbo Muffler. Its patented flow directors and large internal tubes channel exhaust flow, reduce back pressure, and eliminate turbulence.