Horsepower is actually a made-up measurement. Steam engine pioneer James Watt wanted to compare the effectiveness of his engines against the horse that previously did their work.
Watt defined one horsepower as the equivalent of the energy expended by a single horse lifting 33, pounds one foot in the air from the surface of the Earth in one minute. Not an easy thing to imagine. To further complicate matters, European and Japanese car manufacturers use a metric measurement of horsepower. One metric horsepower is slightly more than one brake-horsepower.
Why the difference? Well, on the part of the car magazines, old habits die hard. There was a time when the kilowatt was the preferred measure.
The higher the number of kilowatts the more powerful the batteries. You might be wondering where torque comes into all this. In simple terms, torque is a different measurement of the work an engine can do, taken from a different part of the engine. The ideal is an engine with lots of both. In the list below, you will find an outline describing the characteristics of brake horsepower, with some comparisons to the traditional concept of horsepower that was described previously.
Brake horsepower is very specific to measuring the horsepower of the engine of a car. The result of this measurement does not include the power loss that is incurred by the engine from the generator, gearbox, or any other individual component inside of the engine.
The torque of the engine is measured by applying break to the flywheel, instead of using a torque converter like you would in order to measure traditional horsepower.
In other words, it does not require any additional tools to find the brake horsepower, which is something that the two units do not have in common. After reading all about what horsepower is and how it can apply to the brakes of your vehicle, it is realistic that you would become curious about how to find out the brake horsepower in your own car.
In this section, we will be going over how you can calculate this number. Take a look at the simple breakdown that is listed below. It will explain the process of calculating horsepower with just one easy equation involving only two steps. In order to calculate the horsepower of your car, you will need to multiply the torque and engine speed together.
This will obviously require you to find the values of these credentials before you are able to begin your calculations. After you have found these values, you will be able to plug them in to the horsepower equation, which will involve dividing the entire result by the average rate of radians per second that define horsepower, which is 5, radians.
For a more simple explanation of this concept, the list down below will outline the actual formula of this equation. With the values that you have located, from the engine speed to the torque, you will be able to easily plug them in and find the actual horsepower levels of your vehicle.
As you can see, the formula for the horsepower equation begins with multiplying the speed of the engine by the torque. This step should be completed first, since it is in parenthesis.
The result of this calculation should then be divided by 5, radians, which will ultimately return the result of the horsepower levels in your vehicle. As you can see, calculating the horsepower of your very own car or truck is not only possible, but it is also a very simple process.
Through the multiplication and division of three simple values, you are able to return the final result of horsepower. For a more simple way to find the brake horsepower of your car, without doing any math, you can conduct a test instead. Advertisement Single Stops The single stop from maximum vehicle speed is a relatively simple and straight forward test. On a high-speed test track, the vehicle is accelerated to its maximum speed and braked in one continuous event to a stop.
The manufacturer will define its expectations for the rate of deceleration. This is generally between 0. This is an important factor as this determines the amount of time associated with the energy conversion. The energy of a Corvette at mph is constant. The power necessary to stop it at maximum deceleration is approximately double than if allowed to stop at 0.
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It is important to be able to measure temperature in very small time intervals and in many places. The temperature can vary widely within a small distance. The peak temperature measured at the components and how long it stays above a certain temperature are compared to the particular material specifications for compliance. Typically, things like melting of speed sensor wires, caliper dust boots and steering tie-rod boots are evaluated. In addition to visually obvious failures, things like the thermal limits of the electronics in the speed sensor are also validated.
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Technicians should inspect replacement rotors carefully and compare them in detail to the OE rotor to ensure that thermal integrity can be maintained.
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