I was discussing this with a friend and we imagine what is done is similar to how they boost electric golf cart performance. Not sure if EFILive would have access to those settings in the E78, so possibly some additional tweaking to get that kind of juice out of it.
FWIW I used to PDI them (Pre Delivery Inspection) stock at the bowtie dealer when they first came out, and they will do a burnout to the top of the parking garage.
Due to having the torque of a V6 Camaro... at 0 RPM!