Horsepower Estimate?
Its weight and mph=hp period
Period is a little strong, There's no way it's 100% correct a 100% of the time.
Obviously the formula got to be based on some kind of average hp since we're at peak only top of each gear and maybe at the finish line, and with a certain average hp there must be a general average peak hp but even engines with the same peak can have very different power curves (averages).
Plus factor in air quality, altitude, temp, tune etc..
What about things like 904 vs 727, 904 should be quicker on the track than a 727 even with same engine hp etc...