If you can see the casting mark on the exhaust's port (might be pretty difficult without the heads off the car, or perhaps may use some kind of mirror), give us that, then we can give you more information. It will be four characters (such as D0AE). Look at the next port over from that, I think you'll see another letter there (like an H, or GA). From that, it should be possible to know what you have.
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