The F30 335i you see below has its N55 turbocharged and direct injected 3.0 liter inline-6 controlled by the Motec M182. You will also notice it is a stripped out race car. So how does the M182 help a street application? Well, it does not help you if you want to retain all of your OEM electronic systems.
However, a future answer for those who want to do turbo upgrades on the F30 335i and F32 435i may be relying on such an ECU run in conjunction with the factory DME. The Motec ECU in such a scenario would handle the engine management while the BMW engine computer would make sure all the factory electronics still play nice. This sort of dual ECU solution was employed on the E46 M3 early on with turbo kits and Motec ECU's are used in the high powered Lamborghini and Ferrari Underground Racing turbocharged street cars we all know and love.
This may be the route tuning takes as it is just now the factory computer on the over a decade old E46 M3 is decrypted to the point of allowing turbo kits tuned on the factory DME. With F30 encryption being even more difficult to crack does anyone really want to wait around for 10+ years (could be far less, could be more) for factory DME tuning to evolve to the point of supporting a turbo upgrade?
Fortunately companies like Motec continue to deliver engine control systems that can support modern engine management. It's up to the BMW aftermarket to figure out how to best integrate them.
Look at this dyno of M182 controlled N55 with upgraded Borg Warner turbocharger (stock injectors and fuel pumps) versus OEM DME controlled N55 with the factory turbocharger. This previews what the N55 is capable of with a turbo upgrade. Horsepower is 599.4 with torque at 629 pound-feet:
Pictures and specifications: