Here is a photo of a 1-series with 235/40/18 NT05 on a 18x8.5" ET38 ARC-8.
We suggest that you pull the alignment pins to maximize negative camber for better fender clearance if you plan to run this tire size, since your wheel is 3mm more aggressive than the wheels shown. With the 225/40/18, you would have a slight stretch and that would provide better fender clearance if you lower the car. Added negative camber would be beneficial even though not required, as the 18x8.5" ET35 is on the aggressive side for a 1-series and past where the fender is.