check this out
basically a muffler delete but keeping the quad setup...
Edit: Dont know if the hartage quad and the iCarbon have the same positioning for the pipes. Might have to do some research on that...
2010 AW/BLK 135i
VM 6465 Single Turbo, JB4 + MHD, VRSF CP & Tial, Big Tom, Fuel-It PI + Stage 3 + Return + Ethanol Sensor, BMW PE, MFactory LSD, Spec 3+ & MFactory SMFW, RB External PCV
Best stock turbo 12.5 @ 19.46 spinning all the way down
RIP 2008 AW/BL 135i