What is torque
You may have heard the word “torque” referenced in action movies, car ads or among car enthusiasts but you may still be wondering, “What is torque?” Let’s find out.
Torque is a rotational force applied to a pivot point via a lever. Imagine a bolt that you’re tightening with a wrench that is one foot long. The rotational or twisting force that you apply to the wrench is transferred to the bolt. This force is torque, typically measured in pounds-feet (lb-ft). In this example, by using a footlong wrench to apply one pound of force to the bolt you’re tightening, you’ve just exerted one pound-foot of torque on the bolt. You could increase the torque by either applying more force or lengthening the wrench.
What is torque in cars?
In a car engine, torque is produced by the up-and-down motion of the pistons acting to rotate the crankshaft. This rotational force is then transferred to the wheels via the transmission and drivetrain. A high torque output at lower engine speeds (measured in revolutions per minute or RPM) is what helps some cars go from 0-60 in seconds flat. There are several variables that can affect torque output such as engine size, fuel type, gearing and more.
Torque vs. horsepower
Torque and horsepower are closely related to each other, but still distinct. You’ll often see manufacturers list measurements for both when advertising a car to buyers. As you know, torque is a type of force. Torque is helpful for quick acceleration or for getting a lot of weight in motion. That’s why pickup trucks and other vehicles designed for heavy-duty work often boast high torque outputs.
The difference between torque and horsepower is that torque is the capacity to do work, while horsepower is how quickly that work can be done. Think of it a little bit like two athletes who each lift a 100-pound weight. One struggles and grunts while gradually heaving it overhead, while the other hoists it up in a single, explosive jerk. Both have done the same amount of work, but the one who does it quickly is generating much more power.
In cars, once torque gets you going, horsepower is what keeps you going and helps you reach maximum speed. Both measurements matter when trying to understand how your engine will perform. High torque will give you a quick start from a dead stop, while high horsepower will allow you to reach a greater top speed and sustain it.
Torque in different engines
As mentioned earlier, torque output can vary based on several factors, including engine design. Here’s how torque output can vary across alternatives to the gasoline engine:
A diesel engine requires a higher fuel compression ratio, resulting in greater force being applied to the pistons and subsequently, more torque. Diesel engines are also typically larger as a result of this, which leads to the pistons having a longer “lever” end, which further increases the torque output. These engines also reach max torque at a lower RPM. A diesel engine tends to produce more torque than a gasoline engine, which is why so many heavy-duty vehicles favor diesel.
Electric vehicles are true torque superstars. Internal combustion engines like gasoline and diesel take some time to get cranking because of wasted energy in getting the engine parts moving or through loss of energy as it’s transferred through various gears. Electric vehicles, on the other hand, typically deliver power directly to the wheels, almost instantly. It’s like turning on a blender and seeing the blades start whirring right away. This maximum torque, delivered on demand, is why even lower-end electric vehicles often have a surprisingly zippy 0-60 mph acceleration in seconds.
So, the next time someone around you asks, “What is torque?”, you’ll be ready to inform them. Torque is a rotational force that helps cars accelerate and haul weight. The more torque a car has at lower RPMs, the greater its capacity to do heavy work. While torque is closely related to horsepower, it’s not the same thing.