| Headers are a pain to install. However on US spec E46 M3's you will see significant gains in power by adding headers because our cats are located in our headers. As far as install price I couldn't really say. I do know that a lot of owners are buying the Ebay header for a couple hundred bucks and are very pleased with them. They are essentially a knock off of the supersprint headers.
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Supersprint Race | Streamline Filter | Streamline Air Duct | Autosolutions SSK | OEM ZCP 245/275 RE01-R |