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      12-08-2010, 10:16 AM   #4
BT M3
Second Lieutenant
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Drives: 2010 M3
Join Date: May 2010
Location: MA

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This is incorrect information from my dyno findings. A proper custom tune will yield 15-20whp. And the secondary cats are maybe worth 10hp and some noise. The primaries delete are worth alot more as the design is far more restrictive.