Great horsepower determines true performance  (Dieselpartsworld) 2016-01-17   

Great horsepower determines true performance!
In the end the big horse power of the car run fast, or the big torque of the car run fast? From the formula, we can know the big horsepower is "high speed still retains high torque values" is said to have high horsepower, not only the low speed torque is better, even at high speed torque must continue to maintain, which means that the torque and horsepower of the argument root is redundant, as long as it can achieve high horsepower, except that the torque of the speed region are great outside, on behalf of material technology superiority, the pistons, into the exhaust valve material and weight to be strengthened and lightweight, can be the engine speed increase.
Derivation of torque and power conversion formula
Assuming a circle of radius R (m), torque T (n-m), force F=T/r in the tangent direction of the circumference, the power is defined as "every second of the work", for the circumference activities, rotates a circle: f * circumferential length of 2 pi r will F=T/ r substituted in the calculation, each circle work Work=F * 2 pi (r = - T/r) x 2 pi r = 2 pi t
Then take the engine speed rpm is done every minute, but the power of the P unit is N-m/sec, so it is required to be divided by 60, converted into the work done per second. Into the formula: P=T2 rpm/60 PI, the constant after finishing, can be P (kW) =Trpm/9545.
From above shows that a car's power is transferred from the engine to the wheels, after multiple sets of gear therefore a bit of a loss, if HP DIN is the transfer of power to the wheels, then the same engine power output in different models should be different, try to get a bmw330 bmw530 comparison and the power are is 225hp/5900rpm. Conclusion, or BMW fraud in the data, either it measured is net output of the engine.