This homemade kit allowed my N55 35i to utilize the double intake openings that the X5D is designed with.
I bought the OEM intake duct from the dealership for 35d (part #13718570289) and then sourced the hose and clamps to adapt to the intake box.
No idea if there’s any real power gains but the butt dyno liked it and I felt good knowing both intake ducts were open and feeding air.
All in I spent around $225. The intake duct alone is like $150+.
Located in Charlotte, NC.
Price includes shipping.