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You are bound to have stumbled upon the term Horsepower, whether you own a vehicle or not. HP is a measurement which is used during ads for cars, and it’s also something that you will often hear being used by those who work in machine shops, or even men who are car enthusiasts, but what about the term Brake Horsepower, or BHP? The difference between the two is what we will now uncover.

First, let’s start with what HP is all about. Invented by James Watt, horsepower originally measured the amount of work, that a horse lifting coal out of a coal mine, could do in a minute. Back then, one HP equated to 33,000 foot-pounds. Today, you can easily convert HP into different units, like 1 HP that equates to 746 Watts. It can also be converted into British Thermal Units, or BTU, joules and calories.

However, the most common use of HP, as a unit, is to measure the power of an engine ‘“ which you can determine by hooking it to a dynamometer. What HP actually measures, is the maximum rate of acceleration and the top speed of the car.

On the other hand, Brake Horsepower measures the HP of an engine without considering the loss in power that is caused by some parts of the engine, like the generator, gearbox, water pump and other auxiliary parts.

There are actually no other key differences between BHP and HP, other than the fact that when BHP is measured, the engine torque is determined by applying a break to the flywheel ‘“ as opposed to using a torque converter, like in the case of HP.

To summerize, HP is measured with all the accoutrements attached to the engine, to determine its maximum rate and speed. BHP, on the other hand, is more of a theoretical calculation, which is made under lab-controlled conditions, and without having anything attached to the engine.

Summary:

1. HP is the output horsepower rating of an engine, while BHP is the input brake horsepower of an engine.

2. B HP is the measurement of an engine’s power without any power losses, while HP is BHP less the power losses.

3. HP is measured by hooking up the engine to a dynamometer, while BHP is measured in a controlled environment without anything attached to the engine.