What is the power and torque of an engine?

Power measures how quickly an engine can do work, while torque represents the twisting force available at the crankshaft. In driving terms, torque helps you get moving off the line, and power helps you sustain speed as engine RPM climbs.

Power is typically expressed in kilowatts (kW) or horsepower (hp), and torque in newton-meters (Nm) or pound-feet (lb-ft). The two are linked by how fast the engine is turning: mechanical power equals torque times angular velocity, P = τ × ω. In practical terms, horsepower rises with RPM, while torque is often highest at lower-to-mid RPMs, though turbocharged or diesel engines can push strong torque into higher revs. For quick reference, horsepower can be estimated from torque and RPM with HP ≈ (τ × RPM) / 5252 when torque is in lb-ft and RPM is the engine speed.

How power and torque define an engine’s performance

Understanding these figures helps you gauge how an engine will feel in real-world driving: low-end torque affects acceleration off the line and in gears, while high-end power affects maximum speed and performance at high RPMs.

Key concepts

Below are the essential ideas you need to interpret engine data accurately.

Power and torque are peak values that occur at specific engine speeds (RPM). Real-world performance depends on the entire torque and power curves, not just the peaks.



• Power (kW or hp) is the rate at which the engine can do work, and it generally rises with RPM.


• Torque (Nm or lb-ft) is the twisting force, and it is often greatest at lower to mid RPMs, especially in naturally aspirated engines; turbocharged and diesel engines can maintain higher torque over a broader range.


• Power and torque are connected by the engine’s rotational speed: P = τ × ω, with ω = 2π × RPM / 60.


• Units and conversions matter: 1 kW ≈ 1.341 hp, 1 Nm ≈ 0.7376 lb-ft, and 1 hp ≈ 0.746 kW.


• Measurement methods differ: brake horsepower (absent losses) versus net engine power (SAE net), and dyno type (engine vs. chassis) can affect the numbers you see.


• Reading curves matters: torque curves show twist across RPM; power curves show how fast the engine can do work at each RPM. Diesel engines typically peak torque at lower RPM; turbocharged engines push peak power higher with boost.

Interpreting these concepts helps you compare engines more effectively than looking at a single number alone.

Typical ranges by engine class

Representative figures illustrate how power and torque differ across common engine designs. Values vary by market, tuning, and whether the engine is turbocharged, naturally aspirated, or part of a hybrid system.

Below are representative ranges for modern passenger cars and light trucks as of 2024–2025. Values shown are typical for new engines and may vary by model and market.

These ranges provide a sense of scale across engine types and are not exact specs for every model.



• Subcompact and compact gasoline engines: roughly 50–150 kW (70–200 hp) and 100–250 Nm of torque.


• Midsize gasoline turbo engines: roughly 120–260 kW (160–350 hp) and 200–500 Nm of torque.


• High-performance petrol engines (V6/V8, often turbocharged): roughly 250–500+ kW (335–670+ hp) and 400–900+ Nm of torque.


• Diesel engines in passenger cars and light trucks: roughly 70–250 kW (95–335 hp) and 250–800+ Nm of torque.


• Hybrid and plug-in hybrid systems: engine power often combines with electric motors; combined outputs commonly range from ~100–400+ kW, with electric torque contributing hundreds of Nm (often 200–1,000 Nm from the motor side alone).

These ranges reflect typical contemporary designs, including turbocharging, direct injection, and, for hybrids, electric motor contribution. The exact numbers for a given model depend on tuning, intended use, and market regulations.

Reading curves and real-world impact

To translate numbers into driving feel, consider how torque and power unfold across RPM. A strong torque curve at low RPM delivers quick off-the-line response and confident hill climbs. A steep power curve at higher RPM supports sustained acceleration and higher top speeds. Transmission gearing, final-drive ratios, and vehicle weight all shape how those engine figures translate into actual performance on the road.

Summary

Power and torque describe an engine’s ability to do work and to apply twisting force, respectively. Power governs speed at higher RPMs, while torque governs initial acceleration and pulling power. They are linked by the engine’s RPM through the fundamental equation P = τ × ω, and are reported in kilowatts (or horsepower) and newton-meters (or pound-feet). Real-world performance depends on the full shapes of the power and torque curves, as well as the drivetrain, gearing, and vehicle weight. Understanding both figures—and how they vary with RPM—gives a complete picture of an engine’s capabilities.

What does 1500CC engine mean?

1.5-litre engine
For instance, a car with a 1000 CC engine can displace 1000 cubic centimetres of the air and fuel mixture and would be described as a 1.0-litre engine. Similarly, a 1500CC engine is commonly described as a 1.5-litre engine.

What is power and torque in an engine?

Torque is the rotational force of an engine, which determines its "grunt" or pulling power, while horsepower is the rate at which that force is applied over time, indicating overall performance. Torque is the force that gets a vehicle moving from a standstill, and horsepower is what determines how fast it can go. Both are calculated using torque and engine speed (RPM), but they measure different aspects of performance, with torque relating to how much work can be done and horsepower relating to how quickly that work can be done. 
This video explains the relationship between torque and horsepower with a simple analogy: 1mMoto ControlYouTube · Dec 11, 2022
Torque

• What it is: The twisting force that turns the crankshaft, measured in pound-feet (lb-ft) or Newton-meters (Nm). 
• What it does: It's the force that pushes the vehicle forward from a stop and is crucial for towing and hauling heavy loads. 
• What it feels like: The "slam" in the back of your seat when you accelerate. 

Horsepower

• What it is: A measure of how quickly the engine's torque can do work, calculated by multiplying torque by engine speed (RPM). 
• What it does: It's the measure of the engine's total power and is what allows a vehicle to achieve higher speeds. 
• How to calculate it: The formula is Horsepower=(Torque×RPM)÷5252cap H o r s e p o w e r equals open paren cap T o r q u e cross cap R cap P cap M close paren divided by 5252𝐻𝑜𝑟𝑠𝑒𝑝𝑜𝑤𝑒𝑟=(𝑇𝑜𝑟𝑞𝑢𝑒×𝑅𝑃𝑀)÷5252. 

How they relate

• Horsepower is derived from torque and engine speed, meaning a high-torque engine will have high horsepower if it can maintain that torque at a high RPM. 
• For example, a diesel truck engine might produce high torque at a low RPM to pull heavy loads, while a sports car engine will have high horsepower at a high RPM to achieve a high top speed. 
• The relative importance depends on your needs:
  • High torque: Is better for tasks like towing, hauling, and off-roading, where you need low-end pulling power. 
  • High horsepower: Is better for racing and achieving high top speeds. 

This video explains how to calculate horsepower from torque and RPM: 1mEngineering ExplainedYouTube · Jan 17, 2018

What is torque vs HP?

Torque is the twisting force that causes acceleration, while horsepower is a measure of how quickly that work can be done, which determines a vehicle's top speed. Torque is the "grunt" or force you feel when a vehicle starts moving, while horsepower is the sustained power that allows it to continue accelerating and maintain a high speed. They are directly related, as horsepower is calculated by multiplying torque by RPM (revolutions per minute). 
This video explains the difference between torque and horsepower with simple analogies: 59sdriving 4 answersYouTube · Aug 20, 2023
Torque

• What it is: The rotational force an engine produces to turn the crankshaft. It's the twisting force that makes a vehicle move from a standstill. 
• What it does:
  • Provides the initial force for acceleration. 
  • Is crucial for tasks like towing and hauling heavy loads. 
• Analogy: Think of it as the force of a single punch. 

Horsepower

• What it is: A measure of the rate at which work is done over time. It's a combination of torque and engine speed (RPM). 
• What it does:
  • Determines a vehicle's top speed. 
  • Indicates how fast the engine can do work. 
• Analogy: Think of it as the total damage after a series of punches over a minute. 

This video explains how torque is generated in an engine and its relationship with horsepower: 56sBlack Square PhotographyYouTube · Mar 20, 2021
Relationship

• The formula: Horsepower=(Torque×RPM)/5252cap H o r s e p o w e r equals open paren cap T o r q u e cross cap R cap P cap M close paren / 5252𝐻𝑜𝑟𝑠𝑒𝑝𝑜𝑤𝑒𝑟=(𝑇𝑜𝑟𝑞𝑢𝑒×𝑅𝑃𝑀)/5252. 
• How they work together: You cannot have horsepower without torque. To increase horsepower, you can increase torque, increase RPMs, or both. 
• Real-world example: A large diesel truck might have high torque for pulling power but lower horsepower, while a high-revving sports car will have higher horsepower for its top speed. 

This video explains the relationship between horsepower and torque using the same analogy as the first video, but with more technical details: 1mEngineering ExplainedYouTube · Jan 17, 2018

What does 150 PS mean in cars?

It is also referred to as metric horsepower. For example, 150 PS is equivalent to 147.9 BHP, typically you would see the BHP rounded up to 148 BHP in this example. Kilowatts or kW is sometimes used by the European manufacturers as this is the EU's standard of measurement.