Why do we use horsepower to talk about automotive performance? What do horses have to do with a car engine?

These are very common doubts and there is a very plausible explanation for why we use “horses” to talk about power. In this article we will explain the reason for the term “horsepower”, as well as its importance in the vehicle reprogramming process!

What is horsepower?

Horsepower, also called horsepower (HP) , is a term that refers to the power of an engine.

In technical terms, power is the useful energy generated by the engine, which, simply put, can be said to be the “acceleration capacity” of the vehicle.

In advertising materials, engine power is illustrated in tests of how long the car takes to reach 100 km/h. However, what does the horse have to do with an engine? 

When was horsepower invented and why is it called that? 

The origin of horsepower is in 1768, when engineer James Watt invented the steam engine. At the time, this was the first engine of its kind, so there was no way to compare it and define its power in this way, as the most common means of transport were horses.

Faced with this impasse, Watt placed the horses (the animals themselves) on a treadmill, so that he could measure the energy they generated. Hence the reason for the “horsepower” of power.

The measurement was based on the force that a horse generated in 1 second to lift a 75kg object to a height of 1 meter. 

James Watt's findings indicated that horses generate approximately 745,7 Watts, which became known as 1 Horsepower (HP). However, in some countries, including Brazil, the term "cavalo-vapor" (CV) is also used.

What is the difference between CV and HP?

First of all, HP is the English abbreviation for Horsepower , which translates to something like "horsepower". Therefore, HP and CV are terms used to describe an engine's power, but they cannot be used interchangeably.

This is because they are units of measurement that have different values. For this reason, it's common for these terms not to be used in technical documents. The unit of measurement used in this context is Watts.

In this sense, converting CV and HP to Watts, we have:

• 1 CV = 735,5 Watts
• 1 HP = 745,7 Watts

Therefore, it is clear that horsepower has "less" power than horsepower . For example, a 100 HP engine would have about 1000 Watts more than a 100 CV engine.

Thus, we can see that the difference between CV and HP has the same logic as the difference between pounds and kilograms. That is, despite being units of measurement for mass, pounds and kg are measured with different values.

Is there a difference between horsepower and torque?

Another term that generates a lot of confusion is torque, which is usually used in the same context as power. However, each one plays a different role when analyzing the performance of a vehicle, for example.

In short, and without going into technical definitions, we can say that:

• Modules: ability of an engine to maintain acceleration;
• Torque: force that an engine has to bring the vehicle from rest.

Thus, a vehicle with a lot of torque is able to accelerate more quickly. This is quite interesting, for example, for city cars, where accelerating and reaching the desired speed is more important than maintaining high speeds. This also applies to trucks, which need a lot of power to get going.

Power, therefore, has its moment of glory when it comes to maintaining high speeds. This is because the horsepower can be “felt” by the driver when shifting gears or when accelerating to overtake, for example.

How is a vehicle's power measured?

Having understood all the terms about engine power, we still need to understand how it is, in fact, measured.

To measure a vehicle's horsepower, a piece of equipment called a dynamometer is needed . There are several models of this equipment, such as the bench dynamometer, which measures the engine without being mounted on the vehicle in a testing laboratory.

On the other hand, there are roller or chassis dynamometers. These are devices in which the car's wheels are supported on rollers, so that they can accelerate without leaving their place.

It is with the help of these rollers and various sensors that a computer is capable of calculating engine power and several other performance metrics. In fact, the dynamometer even allows you to simulate performance during gear changes, curves, inclined tracks, among other scenarios.

The role of horsepower in the remap process

As mentioned, horsepower stands out especially when overtaking, since the vehicle (already in motion) needs to gain speed quickly.

Within a remapping process , the main objective is to increase power. Therefore, measuring horsepower is one of the main indicators of whether the reprogramming was successful.

Without this measurement, it is not possible to understand whether the remap generated power gains, nor to understand how many horsepower the engine gained through the process. In other words, to have precision and quality, measuring the car's power is crucial and, for this, you need the appropriate equipment.

How does reprogramming increase vehicle horsepower?

So, how does a remap increase a car's horsepower ? It turns out that vehicle engines don't leave the factory with their maximum power "enabled." Therefore, cars are limited to perform in the simulated conditions designed at the factory.

In this sense, the remap makes a change to the Electronic Injection Central (ECU) software, allowing these limiters to be removed and, thus, achieving greater performance.

However, why don't vehicles come with maximum power from the factory? We explain why a car doesn't come with a factory remap here.

Strike Brasil It's more than a remap

Brazilian company, with a network of more than 50 units widely distributed throughout Latin America and a history of more than 20 thousand reprogrammed cars, Strike Brasil is indisputably recognized as the highest authority on Remap in the region.

To guarantee this excellence, we have a team of highly trained and specialized engineers, present in more than 15 countries, who develop reprogramming maps based on a rigorous quality standard stipulated by Strike Brasil.

The legitimate Remap of Strike Brasil not only optimizes the performance of your vehicle, but also ensures the authenticity of the service provided. When choosing to remap one of our authorized units, you will receive the Software Certificate of Authenticity, a document that attests to the origin and legitimacy of the service performed. To learn more about the certificate, click here.

Trust in the vast experience and excellence of Strike Brasil to maximize your vehicle's potential and eliminate speed restrictions. Contact Us today and discover how we can significantly improve your driving experience, providing greater safety in critical situations. Accelerate with confidence and performance alongside Strike Brasil.