It's not that hard - HP = watts/745.7 :wink:
There are two relevant old sayings - "HP sells cars, but torque wins races," and "electric motors make maximum torque at 0 rpm"
The real problem is that electric motors aren't good at making horsepower, but HP is the car marketer's main tool. They are great for making gobs of torque, down low, where you want it, but not horsepower. That's because HP depends on RPM.
HP = (torque (ft-lbs) * RPM)/5252
At the instant you mash the go pedal, the motor is making insane amounts of torque, but 0 HP, since the RPM = 0. As motor RPM builds, HP rises if torque stays constant. The problem is that it's hard to keep the motor torque up as the RPM builds, so high RPM HP falls (which is why the S is great off the line but lacks high-speed passing power).
ICE engines can produce lots of torque down low (big displacement V8's, possibly with a supercharger), or go for high HP numbers by keeping the torque up at higher RPMs (small 4 cyl with variable valve timing, 4 valves/cyl, turbos - all keep the engine breathing at high RPM). It's really hard to do both (low RPM torque that doesn't fall off as RPM builds.
What Tesla should do is publish a HP/torque graph. When all the V8 gearheads see the insane low end torque, they'll get it.