[The__J__Factor]

Ummm im just pulling this off the website. Cost is around $AUD390 per muffler.
http://xforce.com.au.tmp.anchor.net.au/cars/view_car/29

You have to get pics off their site since they wont let me copy the image locations to post up here. But the muffler comes in different sizes/styles. So it doesnt have to be a canon like in the video they have normal oval and dual out let ect.

How does it work?
Varex muffler combines both the design technology of the stock muffler and the performance muffler into one single compact unit. A sophisticated butterfly valve mechanism is implemented to redirect the exhaust gas flow and vary between the two. For higher sound level, the exhaust flows are directed through the opening path and produces maximum power with a robust sound level (or the “sports car note”) and near-zero resistance. Whilst for lower sound level, the exhaust flows are directed through the chambered path (similar design with the stock muffler), and produces minimum sound level that gives you the best in-car comfort. Also, you are able to control the angle of the valve which can be adjusted to stop at any point between the sports mode and the silence mode. This gives you further freedom to set the optimal sound level according to your preference.

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