Here a video of a 2013 135i ,,,fully modified,,,this vehicle has been flagged by BMW for being modified and not covered for any emissions anymore,,,,I think the only thing that is covered by BMW is the maintence.,,,the wiring job is done so poorly,,,,that the people installed it the first time they damaged the DME ,,,,and that’s how this vehicle got flagged from BMW ,,,,they had to buy another DME ,,,,,and the installer still didn’t learn there lesson,,,,,the wiring sucks.,,,,the other video is how load the exhaust system is on this car,,,,,I for one like a modified car and exhaust,,,,but this is a little to load,,,,this car has no catalytic converter and no muffler,,,,,,even while driving down the street,,,,it was to load,,,,,I must be getting old.