When selling a car; or rather when a car is being sold to you, the word ‘horsepower’ is often banded about. As the name suggests horsepower is, technically speaking, the amount of hypothetical horses that the engine is capable of replicating the power of. This may seem a little obtuse and extremely inaccurate, but the term came about during the advent of the steam train; and was used as a way to illustrate the number of horses (which the trains were replacing) that was equal to the power of one engine.
Naturally, this number would have been a bit of an estimate as no two horses will have the same efficiency and output, which is why it has since been refined into a more concrete term. Specifically 1 horsepower is equal to 745.7 Watts; a unit which is used to convey the rate at which energy is transferred.
All this is very well and good, but does that mean for sure that a car with a brake horse power of 110 is going to be less powerful than a car of 150? Technically yes, as the engine is inherently more capable of a higher energy output, but this is where the ‘brake’ aspect of horsepower comes in.
A car’s brake horsepower is simply the power an engine’s puts out without all of the energy that is lost inherently through energy transfer, as well as all the various tasks a car has to perform apart from simply moving. Another major factor that can affect a car’s power is its weight, as the heavier the car the more energy has to be expended simply getting its wheels move.
So when you are being sold a car, and you are being told all about how high its brake horsepower is, know that the number they are giving you may well be inaccurate. If you would like to get a more accurate impression of the actual horsepower of a car, ask for the car’s weight, in addition to its horsepower. With this information, and by using our BPH Calculator, you can discover what horsepower a vehicle actually puts out, and you maybe surprised to see the actual difference.