Is there any downside to doing this? Will back pressure be affected, preventing 6-port actuation?
Will they fit in an N/A without mod?

 

They will fit fine, however the car will be slightly louder.

 

They'll work, but they won't provide much of a gain.

 

Yeah, the Turbo exhaust isn't much less restrictive that the NA. Plus it'll probably cost more to get new ones from Mazda than go aftermarket.

 

Exactly, why would you even try to get stock muflers?

 

I'm not looking for performance, I just need some okay mufflers. Just wanted to know if stock T2's will work in case I come across some used ones. Sounds like they would be okay.

 

Yeah, I know someone that wanted to replace his rusted up n/a exhaust. He found some Turbo mufflers at the junkyard and they worked fine.

 

I have Series 5 T2 mufflers on my '88 Vert. I went with them primarily because they were quieter than the round NA versions. The soft top isn't near as sound insulative as a hardtop coup, so that is a good thing.

BUT, I have to also say that after installing them there was a noticable seat of the pants difference better performance with the T2 mufflers. So, perhaps they are less restictive.

BUT, when I grow up, putting a set of Racing Beat's on my Vert is on my to do list.

By the way, at Racing Beat they have the '68 Cosmo that was at 7Stock. Mazda contracted Racing Beat to completely redo the drivetrane to good working order. I think the game plan is to use it for a RX8 road show to show the Wankle roots. Since I have a good friend that works there, I was able to give it a good first hand check out including the 10A engine that was on the bench being rebuilt. It was all I could do to hide my drooling. Very cool.

 

They'll fit fine. It's difficult to find a muffler that flows as well as the TII mufflers.

 

I hope the rebuilt '68 Cosmo is to show off the Cosmo 21 concept! I have heard the TII "Y" pipe is also bigger than NA "Y" (Racing Beat site says something about their "Y" being upgrade for NA, but same as TII-I believe), so maybe you want to replace the whole catcack if you go this route-you Know the turbo guys who have stock mufflers laying around got full catbacks...