If you want a nice sounding exhaust cheap, buy a catback from a speed owner. I got an OEM MS3 catback for $200 shipped from a Speed 3 owner who was upgrading his exhaust. If you want an intake, I'd suggest the Fujita F5. Got mine for 175 shipped. F2USA sells a cai for the 3 at a pretty nice price too.
If you are worried about staying under warranty, then like someone said, just go to the Mazdaspeed section on Mazdausa.com for the 3. They have a CAI and CBE. They are pricey though and you have to get the Mazda dealer to install it (when you could easily do it yourself) I got my 3 used so I don't worry about these things :P
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[url="http://forums.mazdaworld.org/index.php?showtopic=31314&st=0#entry430695"]<span style="color:#0000FF"> </a>OEM MS3 CBE | Fujita F5 | Progress rear sway | 6000k HID's | yellow fogs | Memphis amp & subs | faux Mazdspeed shift knob| OEM MS3 boot and surround |OEM MS3 Stubby | OEM all weather mats | generic ground/condenser kit | custom painted engine bay
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