Like the post above states, swapping any component of the exhaust system, sans the emissions parts, is usually acceptable. Cool air intakes and exhaust headers used to have a history of being hit-and-miss smog-wise, but it seems to be more common now that a lot of these parts are CARB-exempt. Just do your research before you buy.
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2010 QAB Zed Roadster | Touring | Sport | Navigation
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