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How much horsepower is indicated in the car's passport and what is their real number

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How much horsepower is indicated in the car's passport and what is their real number
How much horsepower is indicated in the car's passport and what is their real number

The more powerful the car, the more its owner pays to the state budget in the form of fees and duties. Nevertheless, there are many fans of fast driving, and they proudly explain to less we althy citizens how much horsepower is hidden under the hood of their “iron horse”. If someone has only sixty of them, then this is practically a small car, but a hundred is already serious. How is it that the engine is priced in horse-drawn units?

how much horsepower

Watt's invention and marketing

It all started from a historical moment, namely, with the invention of his machine by James Watt, which made a revolution in steam engine building (1772). It differed from previous developments in double action, which led to its economy and much better handling. Each engineer is interested in getting the maximum economic effect from his achievement, but any novelty is perceived on the market with caution. This problem was also faced by Watt, who proposed a new steam engine to numerousowners of coal mines. Then "PR technologies" were not yet as developed as they are now, everyone invented advertising moves on their own. It turned out that James Watt was talented not only in mechanics. He also proved himself to be a gifted manager, using the method of comparison that is now common.

how many horsepower 1 kW

How to compare couples and a horse

In order to keep the double-acting steam engine interested in future buyers, Watt had to omit the physical and technical details. In them, the mine owners still did not understand anything. Consumers were interested in one thing - how much profit this device would bring them.

The lifting of coal at that time was carried out by horse traction. By illustrating how much horsepower his car could replace, Watt could make a convincing case for the financial benefits of buying it.

Here you should pay attention to the fact that the usual horse-drawn animal was too large for use in underground workings, so ponies worked in the mines. This, in a certain sense, played into the hands of Watt (in parrots, as you know, the boa constrictor is much longer). The numbers could be impressive.

horse power

Process of business case and unit of measurement

The great inventor had to take a break from complex engineering calculations for a while and do arithmetic combined with observations of animals and miners. He calculated that, on average, per minute, a load of 180 pounds (a little over 80 kg) is lifted by a pony to a height of 181 feet.(about 55 meters). Multiplying these two numbers, Watt came up with a product of 32,580 pound-feet, then rounded it up to 33,000 to simplify the calculations. Now all that was left was to install the machine, determine its performance, divide it by 33,000, and name its horsepower. Simple and clear. A pump equipped with a Watt machine can replace such and such a number of horses. Further economic calculations are available to any accountant who has information about the costs of maintaining ponies, their cost and other expenses. The comparison showed a greater profitability of a pair in comparison with a horse. Progress won.

Pony are also horses

About the fact that not full-fledged horses, but ponies, were used as a standard, somehow it was forgotten over time. But horses are different - and carts, and horses, and ordinary savras. Over time, the Americans even offered their own “standard”: according to their opinion, an animal weighing 750 kg develops a power of one horsepower, jumping over an obstacle of a square section with a side of 183 cm (American Scientist magazine). Since no one could really justify where these numbers came from, the definition did not stick.

However, Watt's experiments were recognized by physicists and engineers. They gave his name to a unit of power, for the first time in history naming it after the inventor. It happened in 1882, Amps and Volts were still ahead. It remained to unequivocally determine how much horsepower a watt has.

What is the difference between American and European horsepower


Throughout Europe (including the Russian Empire), power by that time was calculated based on another system unit - a kilogram of force, and speed, measured in meters per second. It turned out that 1 liter. With. was equal to 75 kgf m/s. Now it was easy to determine how much horsepower 1 kW included. Comparing the measures taken historically, metrologists considered that 1 liter. With. corresponds to approximately 735.5 watts (more precisely - 735.4988) in the metric system.

The British and Americans use their own measures of forces and weights, so their numbers are slightly different from ours. In the US, the horse is slightly "stronger", rated at 0.745699871 kW. However, in the end, this does not particularly affect the result, the difference from the metric 1 liter. With. is just over one percent.

Marketing Tricks

Horsepower is one of the main advertising baits when selling cars. When buying a powerful car, many consumers believe that they themselves become stronger, and sellers are in no hurry to dissuade them from this, quite the contrary. Even if the engine is indeed comparable to the engine of a World War II fighter, I would like the figure to be even more solid. Of course, it’s not good to deceive people, they can be sued for it, but you can measure power in different ways. There are two main methods for increasing nameplate power:

1. "Net measurement". The method is the most common, except that the engine is running on a stand, without a silencer, and only for a reference load. If everything were connected to it, without which no car can drive, butnamely the transmission, generator, radiator fan, etc., then, in comparison with the gross measurement, the power would differ by at least a fifth. Downward, of course.

2. Fuel tricks. To determine how much horsepower an engine can put out, it is fueled with the highest octane gasoline available on the market. In some countries, even 100 brand aviation fuel is sold at gas stations, and automakers (especially Japanese) use it with might and main. It is possible that it is they who sponsor the sale of such gasoline, because the mass consumer practically does not need it, but the very fact of free access to it allows you to test the engine in a critical mode and get very good results.

Such a marketing knack. And at the same time, no fraud, everything is honest.

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