Up-grade your headers when you do a turbo up-grade.. the stock headers are more than capable enough to cope with the stock turbo and minor mods
IMO I would get a 3 inch
TBE but find a system that has a cat in the dump pipe or and oval tip muffler. I was running one originally and was perfect for what your after a lot quieter than I expected but still had that boxer rumble. I prefer super loud so I opted to go for a full Cat-less system!
Check out Ultrex performance! Best bang for your buck an exactly what your looking for.
Good luck!
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