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      07-28-2012, 06:45 PM   #11
flinchy
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Drives: 130i
Join Date: Nov 2011
Location: QLD, Australia

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Quote:
Originally Posted by JimD
Magnaflow's cat back is 2.5 inch tubing. It is also mandrel bent - smoother bends = less restriction.
The stock one in mine is mandrel except for a single press around the diff, as well as the res/cats/muffler being really restrictive

And of course the stock bends not being as efficient as possible