Horsepower = (Torque x RPM) / 5252.
A dynamometer can either directly measure torque output by measuring the force exerted on the rollers, or can directly measure horsepower by measuring the acceleration of a weighted roller. It then calculates the unknown value based on the RPM and the measurement.
You will see that HP and TQ always cross (are equal) at 5,252 RPM on the graph. This is because of the division in the formula above. Below that point, the torque is greater, and above that point, the horsepower will peak.
Other than seeing peak numbers and your power curves, you can use this information to help drive your car better. For instance if you are a drag racer and want to know where to shift, you can see at what RPM your horsepower starts to fall off and know to shift when the power starts to fall off. You can also see if you have any issues with your tune or other problems if there is any kind of weird activity on your graph.
Torque is the measurement of turning force. A wrench applies torque to a bolt. A motor or engine provides torque to do work. Horsepower is the measurement of the work done or ability to do work. This is done by taking the speed the engine is operating at (RPM) and what torque it is producing and applying a formula to give a horsepower rating.
Toruqe is the amount of rotational force the engine generates. Horsepower is work performed in a straight line.
Toruqe is the amount of rotational force the engine generates. Horsepower is work performed in a straight line.
Horsepower is defined as work done over time. The exact definition of one horsepower is 33,000 lb.ft./minute. Put another way, if you were to lift 33,000 pounds one foot over a period of one minute, you would have been working at the rate of one horsepower. In this case, you'd have expended one horsepower-minute of energy. There are other definitions but as a whole they say approximately the same as in energy consumed for actual work.
Torque has nothing to do with horsepower. It is purely a measure of force, whereas horsepower is a measure of how much work can be done over time.
Horsepower and torque in lawnmowers are key indicators of their performance. Horsepower measures the engine's overall power output, affecting how quickly the mower can cut through thick grass, while torque represents the engine's ability to perform work, particularly at low speeds. Higher torque is beneficial for tackling tough terrain or dense grass, whereas horsepower is more relevant for overall speed and efficiency. Choosing the right balance of both depends on the specific mowing tasks and lawn conditions.
There is not a direct answer to your question due to you are asking about engine size/displacement. The amount of "work" an engine can accomplish is related to the torque that is output from an engine. The amount of torque an 80cc engine can produce is also variable. For example, a screaming 2 stroke run at 12,000 rpm does not have much torque -- it relies on the engine momentum to do work. A 4 stroke 80cc engine would have more "torque" (but less horsepower) There is also a gearbox you have to include. A large reduction gearbox that turns slow for the high engine rpm could output hundreds of pounds of torque (foot pounds or pound feet) translating to pushing thousands of pounds.
The difference between brake horsepower and horsepower or wheel horsepower, they are the same thing, is that brake horse power is the power produced by the crank. The wheel horsepower is the amount of power delivered to the wheels. Brake horsepower refers to the method used to test the engine. A brake is attached to the engine and used to maintain the engine at a constant RPM at full throttle. The delivered power output is then a simple calculation of RPM times torque. Horse power is based on the average amount of work that a horse could do in a day. It is taken to be 746watts. well you guessed it engine output is also specified in kilowatts so divide by 746 and you have horsepower. As stated above it is all the same thing. There is a difference between advertised horsepower and brake horsepower. Advertised horsepower is what a manufacturer will rate its engine/automobile/machine to produce. Brake horsepower is the actual measured horsepower, for example, of a motor on an engine dynamometer.
Horsepower - power over time, continuously used. You can only generate what you need or use.Torque- Power on hand, waiting for demand. Like a weight hanging on stick. It is there when you need it.Torque gets you going and Horsepower keeps you rolling.AnswerYou really should be asking, "What is the difference between torque and power?"Horsepower is simply the Imperial unit of measurement for power, usually used to describe the output (rather than input) power of a machine. These days, most countries use watts, which is the SI unit for power. Power is defined as the rate of doing work. In Europe and elsewhere outside North America, the output power of a car engine is measured in kilowatts, rather than in horsepower.Torque is the product of the radius of rotation and the force acting at right angles to that radius. So, torque is normally expressed in newton metres.The work done by torque can be determined by multiplying the force acting at right angles to the radius, by the circumference through which that force acts. If we know the time taken to complete the circumference, then it is possible to determine the power.
By Karl Brauer, Editor in Chief, Edmunds.com While horsepower is often considered when shopping for a vehicle, what about that "other" engine rating: torque? Specifically, what are the differences between horsepower and torque? If you flip through the pages of any automotive publication, you'll notice that these two measurements are commonly listed under vehicle specifications. And while the average car enthusiast knows that both horsepower and torque play a role in performance, most of them don't understand exactly how or why. Let's begin by explaining the technical difference between the two. Horsepower is defined as the amount of energy required to lift 550 pounds, one foot, in one second. From this definition you can see that the components of horsepower are force, distance and time. Distance and time are self-explanatory but force, specifically a twisting force, is what torque is all about. Remember that the initial energy that moves a car forward starts in the combustion chamber in the form of an explosion. This explosion forces a piston (or group of pistons) down in a straight line, which pushes on a connecting rod and turns the engine's crankshaft. It's this turning crankshaft where the twisting force of torque initiates. From there the force is carried through a flywheel, transmission, driveshaft, axle(s) and wheel(s) before moving the car. The measurement of torque is stated as pound-feet and represents how much twisting force is at work. If you can imagine a plumber's pipe wrench attached to a rusty drainpipe, torque is the force required to twist that pipe. If the wrench is two feet long, and the plumber pushes with 50 pounds of pressure, he is applying 100 pound-feet of torque (50 pounds x 2 feet) to turn the pipe (depending on the level of rust, this may or may not be enough torque). As you may have noticed, this measurement of torque does not include time. One-hundred pound-feet of torque is always 100 pound-feet torque, whether it is applied for five seconds or five years. So, if you want a quick answer to the difference between horsepower and torque, just keep in mind that horsepower involves the amount of work done in a given time, while torque is simply a measurement of force and is thus a component of horsepower. To see how torque and horsepower interact, imagine your favorite SUV (everyone has one of those, right?) at the base of a steep hill. The engine is idling and the gear lever is in the "Four-Low" position. As the driver begins to press on the throttle, the engine's rpm increases, force is transmitted from the crankshaft to each wheel, and the SUV begins to climb upward. The twisting force going to each wheel as the vehicle moves up the hill is torque. Let's say the engine is at 3,000 rpm, the gear ratio is 3, and the vehicle is creating 300 pound-feet of torque. Using the following formula, we can calculate horsepower: Take the torque of 300 multiplied by a shaftspeed of 1000 (3000 rpm divided by a gear ratio of 3) for a total of 300,000. Divide 300,000 by 5,252 and you get 57.1 horsepower that the SUV is making as it begins to ascend the hill. It is interesting to note that, since 5,252 is used to calculate horsepower by way of torque and shaftspeed, it is also the number in the rpm range at which torque and horsepower are always equal. If you were to view the horsepower and torque curves of various engines, you would notice that they always cross at 5,252 rpm. So now we have a technical understanding of how torque interacts with horsepower, but let's move beyond that to some real-world examples. For instance, we all know that a car moves from a dead stop in 1st or low gear, yet as the car's speed increases, the gears must be moved up through 2nd, 3rd and 4th to maintain acceleration. This is because at low speeds the transmission's gears work to transmit maximum torque from the engine to the wheels. You want this because it takes more force, or torque, to move a vehicle that is at rest than it does to move a vehicle in motion (Newton's 1st Law). At the same time, once a vehicle is underway, you want less torque and more horsepower to maintain a high speed. This is because horsepower is a measurement of work done and includes a time element (such as wheel revolutions per minute necessary to maintain 75 mph). Since entire books have been written on the concepts of horsepower and torque, it's not realistic to try and cover them fully in a single column. Finally, let me leave you with my favorite phrase about the relationship between horsepower and torque: Horsepower is what you read about, torque is what you feel.
By Karl Brauer, Editor in Chief, Edmunds.com While horsepower is often considered when shopping for a vehicle, what about that "other" engine rating: torque? Specifically, what are the differences between horsepower and torque? If you flip through the pages of any automotive publication, you'll notice that these two measurements are commonly listed under vehicle specifications. And while the average car enthusiast knows that both horsepower and torque play a role in performance, most of them don't understand exactly how or why. Let's begin by explaining the technical difference between the two. Horsepower is defined as the amount of energy required to lift 550 pounds, one foot, in one second. From this definition you can see that the components of horsepower are force, distance and time. Distance and time are self-explanatory but force, specifically a twisting force, is what torque is all about. Remember that the initial energy that moves a car forward starts in the combustion chamber in the form of an explosion. This explosion forces a piston (or group of pistons) down in a straight line, which pushes on a connecting rod and turns the engine's crankshaft. It's this turning crankshaft where the twisting force of torque initiates. From there the force is carried through a flywheel, transmission, driveshaft, axle(s) and wheel(s) before moving the car. The measurement of torque is stated as pound-feet and represents how much twisting force is at work. If you can imagine a plumber's pipe wrench attached to a rusty drainpipe, torque is the force required to twist that pipe. If the wrench is two feet long, and the plumber pushes with 50 pounds of pressure, he is applying 100 pound-feet of torque (50 pounds x 2 feet) to turn the pipe (depending on the level of rust, this may or may not be enough torque). As you may have noticed, this measurement of torque does not include time. One-hundred pound-feet of torque is always 100 pound-feet torque, whether it is applied for five seconds or five years. So, if you want a quick answer to the difference between horsepower and torque, just keep in mind that horsepower involves the amount of work done in a given time, while torque is simply a measurement of force and is thus a component of horsepower. To see how torque and horsepower interact, imagine your favorite SUV (everyone has one of those, right?) at the base of a steep hill. The engine is idling and the gear lever is in the "Four-Low" position. As the driver begins to press on the throttle, the engine's rpm increases, force is transmitted from the crankshaft to each wheel, and the SUV begins to climb upward. The twisting force going to each wheel as the vehicle moves up the hill is torque. Let's say the engine is at 3,000 rpm, the gear ratio is 3, and the vehicle is creating 300 pound-feet of torque. Using the following formula, we can calculate horsepower: Take the torque of 300 multiplied by a shaftspeed of 1000 (3000 rpm divided by a gear ratio of 3) for a total of 300,000. Divide 300,000 by 5,252 and you get 57.1 horsepower that the SUV is making as it begins to ascend the hill. It is interesting to note that, since 5,252 is used to calculate horsepower by way of torque and shaftspeed, it is also the number in the rpm range at which torque and horsepower are always equal. If you were to view the horsepower and torque curves of various engines, you would notice that they always cross at 5,252 rpm. So now we have a technical understanding of how torque interacts with horsepower, but let's move beyond that to some real-world examples. For instance, we all know that a car moves from a dead stop in 1st or low gear, yet as the car's speed increases, the gears must be moved up through 2nd, 3rd and 4th to maintain acceleration. This is because at low speeds the transmission's gears work to transmit maximum torque from the engine to the wheels. You want this because it takes more force, or torque, to move a vehicle that is at rest than it does to move a vehicle in motion (Newton's 1st Law). At the same time, once a vehicle is underway, you want less torque and more horsepower to maintain a high speed. This is because horsepower is a measurement of work done and includes a time element (such as wheel revolutions per minute necessary to maintain 75 mph). Since entire books have been written on the concepts of horsepower and torque, it's not realistic to try and cover them fully in a single column. Finally, let me leave you with my favorite phrase about the relationship between horsepower and torque: Horsepower is what you read about, torque is what you feel.
By an engine or machine working ( force x distance = work)