Testing newly installed HPF 3.5 exhaust on my 2009 135i. Car is catless and the exhaust has no muffler, just one resonator. Tune via JB4. Enjoy.\r<br>\r<br>Exhaust notes from the 2013 BMW 135is. Source audio levels for both interior and exterior have not been altered.\r<br>\r<br>2013 135i N55 all stock.\r<br>\r<br>A video clip of the exhaust note of the 135i n55 with DCT box. Driving around using the the paddles and a few short bursts, some downshifts and one WOT for a .\r<br>\r<br>306 HP.
