FWIW, you can get a gadget that stick onto the window of a car to tell you how much horsepower it has. It's a little thing with a reasonable accurate accelerometer, and you feed in the weight of the car and accelerate away, and after a few seconds it'll tell you how much power you used to accelerate that amount of mass that fast, etc.
It's called a G-Tec, and I popped it up on the window of a 747-200, powered by RR RB-211 D4X's, 53,000 lbs rated for T/O.
Allowing for a little derate, I got a grand total of 72,000 hp!