Here she goes:
multiply teh KW by 1.341 to get hp
divide hp by .7455 to get KW
It is because 1 hp is equal to 550 feet per pound per second. this is what the average horse could do: lift 550lbs up one foot in one second. Conversely, it also means it could lift 1 pound 550 feet in 1 second.
1 Kw is 738 feet per pound per second. Why? Im not sure, it isn't really car related
