There is a video on YouTube by IND Distribution that shows probably the first 2023 BMW XM that has been put on a dyno. While putting a powerful SUV on a dyno isn't unusual, getting unexpected test results like these could be.
The IND Distribution team did four runs at the dyno at Performance Eurowerks in Illinois and the highest figures that can be seen in the video are 614.84 hp and 771.65 NM of torque.
This is the output at the wheels and assuming an approximate power loss of around 20%, this would mean the output at the crank is around 768 hp and 965 Nm. Now, BMW itself advertises the XM to have 644 hp and 800 Nm of torque.
Another thing to note here is that the 2023 BMW XM used for the test was not fully charged which could have impacted the output figures. Also, the guys at IND Distribution admit that it is a little difficult to figure out exactly how the hybrid system is functioning while the XM is in dyno mode.
Apparently, the electric power gauge ramps up during the dyno test but spikes earlier than expected. It’s also unclear at the moment whether BMW's dyno-mode employs the electric motor differently from its standard operation, which could potentially mean more power remains hidden and unleashed.