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      08-03-2011, 10:39 AM   #9
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Drives: 2011 E90 M3 ZCP
Join Date: Dec 2010
Location: Houston, TX

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Most performance exhausts are loud at cold start up. The 1M does NOT have an exhaust flap. Check if you don't believe it. The flaps that are found on some BMW models are all vacuum controlled. The additional sound is exhaust drone which is usually louder under load.
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