If you look up behind the rear valance, directly behind the black rotary emblem, you will see a round welded cap on the muffler. It seems like they were intending to offer a center exhaust and due to noise regulations capped it to make a two outlet muffler.

I suspect that we will see some modded exhausts with either 3 outlets or a single center in the near future.

Thoughts?

I think someone should get a drill out and start experimenting!
[Insert sarcastic icon]

Vince

Yeah, the Parts & Service Manager at Mazda South and I took a good look at that while mine was on the hoist for its PDI. He was thinking along the lines of an electronic dump valve and a pipe out through the center of the rotary symbol in the middle of the lower bumper valance. However, I suspect that you'd run into problems with the plastic bumper melting due to the close proximity of that hot pipe; note that the factory dual tailpipes have plenty of clearance around them to prevent that happening.

That said, I would not be at all surprised if someone was to come out with a kit for it.

http://www.artex.co.jp/Pages/Car/RX-8/magazine/Image/afTheStage_03_08_02.jpg

Well given the internal construction of the muffler, as seen in the cutaway, I can see why the cap and why no one will want to take it off... Straight pipe out the back.

Maybe a Y pipe to two mufflers and then back out to the center with another Y to create the outlet.

My Vince you are a sharp one.