If it's unventilated or otherwise unmodified cooling-wise, you probably won't be able to run it at that very long before you melt the phase wires, and short stuff out at the axle. If it manages to not melt the wires, it'll probably melt the solder on the phase wires and disconnect one or more, and save the motor then. (like happened to Dogman once). If that fails to happen, it'll probably cook the windings after a while.
This is based on various reports, troubleshooting, etc., from assorted forum threads I've read or participated in the last couple years, plus my own recent experiences as I now have 4KW on tap to briefly goose my older style 9C 2807 with on CrazyBike2 (or at least I did until I broke the frame in a skid/crash the other day).
With mine, which is ventilated, I can SMELL the (stock) wires overheating, with just bursts of 80-110A battery current, I think it's at 15s right now. I try to keep those under a second or two, but it's kinda fun to be able to accelerate 0-20MPH in under 3 seconds on that big and heavy a bike, and know that if it weren't for the legal limit on ebikes here, I could keep going from there pretty jiffily.
So I am not as easy on it as I should be, and it is often too hot to touch the windings thru the vent holes when I stop.
I can only imagine what it would be like if I had it still sealed up, unventilated! And that is with a very short <2.5mile work commute, which is mostly stop-and-go traffic, with some stretches of 20MPH cruising.