[ZeGermanHam]

There is some variation on the internal design of the Dynomax Superturbos dependent on the case size. I have the smaller 16" 17629 model, and it has a totally different design, without the flow directors that most people think of when discussing superturbo mufflers. They just have the dimples in the outer case (see photo attached).

Although I have Dynomax superturbos currently installed on my car, I think the Summit Racing turbo muffler is a better choice. I also own a pair of those (not installed), and they are better constructed (in the US), cheaper, and don't neck down to 2-1/4" internally like the Dynomax Superturbos do.