Horsepower – All About It

Horsepower – It’s a term that we hear extensively when talking about cars, but what exactly is it? It’s basically a word used to describe the power output of an engine, generally referred to as ‘hp’.

Horsepower, however, isn’t used everywhere. There are other terms to refer to the car’s power, such as PS, CV, bhp, and kW. Each term has its own meaning: ‘ps’ refers to ‘pferdestarke’ which just means horsepower; CV is a French acronym for Chevaux-Vapeur, which again is equivalent to horsepower; bhp, one of the more commonly heard terms, stands for ‘brake horsepower’, and is a UK term; and, finally we have kW, which stands for kilowatt and is more commonly used for electric vehicles.

When referring to bhp and hp, bhp is the power figure at the wheel, and hp is the power figure at the crankshaft, where no power frictional power is lost. But, the difference between the two figures is minute. It is almost at a 1:1 ratio, where 1hp is equal to just under 0.99bhp.

Now, after understanding horsepower and brake horsepower, let us talk about how the term came about. Horsepower wasn’t a proper mechanical measurement, it was a made-up term by James Watt.

In the 1760s, when steam engines were coming about, James Waitt wanted to compare the power of his engines to the horses that they replaced.

He had an idea where he made a horse lift 33,000 pounds of water one foot in the air from the bottom of a 1,000-foot deep well, in one minute, and that result was ‘horse power’.

Nowadays, luckily power of a vehicle is not measured like this, but instead on a Dynamometer, or a Dyno! A dynamometer is a machine that measures the torque and power output of an engine.

While many think more horsepower is more speed, they aren’t entirely correct, nor are they wrong. It only matters in straight-line speed. But, a lot of factors come into play when talking about how it works.

In general, a car with more horsepower will be faster than a car with less horsepower. However, there will be a point at which increasing the horsepower will not result in a corresponding increase in speed. This is because other factors, such as weight and aerodynamics, will start to become more important.

An engine’s power has two figures, Horsepower and Torque. In simple terms, torque helps to pull a car, and horsepower makes the car go fast. In mechanical terms, torque is the turning force of an engine, while power is how hard the engine works.

Diesel cars usually have more torque and less power, whereas Petrol cars have more power and less torque.

Although the name wasn’t made to stick, horsepower is one of the most commonly used terms when referring to power. Also, more power doesn’t necessarily mean higher speeds, but it definitely brings a bigger grin to the face, so why not go for it? After all – Power, baby, Power!