What is Torque in Cars?

Horsepower and torque are the primary measurements of a drivetrain's power. Horsepower, for whatever reason, gets the notoriety and establishes the bragging rights. Yes, more horses mean more power, but horsepower only measures the peak performance capability of an engine or motor and is not a measure of its strength.

What is Torque in Cars

Torque measures the twisting force, or strength, of an engine or motor. That sensation of being pushed back into your seat when you stomp on the accelerator? That's torque. Illustrated using a non-automotive example, when opening a jar, torque is the effort with which you loosen the lid while horsepower is the speed with which you spin it off.

Simply put, torque gets you going, while horsepower keeps you moving. And, depending on how you intend to use your vehicle, one will matter over the other. Torque also works differently based on the engine type and energy source.

How Torque Works in a Gasoline Engine

Torque and horsepower have different characteristics, often peaking at different engine speed ranges, better known as revolutions per minute (rpm).

In an internal combustion engine (ICE), torque performance appears as a bell curve. After torque builds to its peak rpm, it will taper off as horsepower is simultaneously building to its peak rpm. This torque peak is when the engine has reached its most efficient and maximum speed for that torque rating.

Once a car is moving, torque is less important. For example, when cruising on the highway, the engine typically operates in its highest gear and at the lowest possible rpm. Why? Additional torque is no longer necessary to keep the vehicle in motion, so the drivetrain switches to its most efficient operation mode.

Small vehicles usually employ small engines that offer lower torque and horsepower numbers. Their lighter weight and anticipated use by owners means they don't require larger and more powerful engines. Keeping the engines simple also keeps the vehicles affordable and fuel-efficient. But this doesn't imply that all small cars are boring to drive.

The Mazda MX-5 Miata is a prime example of a sports car with less horsepower and torque than its competitors. Still, its low engine ratings hardly take away from its driving dynamics. With a 2.0-liter 4-cylinder engine, the MX-5 Miata produces 181 horsepower at 7,000 rpm and 151 pound-feet of torque at 4,000 rpm. But it also weighs no more than 2,388 pounds and has a nearly perfect weight distribution over the front and rear axles. Its sporty performance comes from its high-revving engine and balanced handling characteristics and not its outright acceleration speed.

How Torque Works in a Diesel Engine

Diesel engines feature more torque at a lower rpm than gasoline engines, which results in better capability for hauling, towing, and climbing because the engine doesn't need to work as hard to get the vehicle moving.

The 2021 Ford F-150 offers an optional 3.0-liter turbodiesel V-6 rated at 250 hp at 3,250 rpm and 440 lb.-ft. of torque starting at a low 1,750 rpm. Within the F-150's engine lineup, the turbodiesel has one of the lowest horsepower ratings but one of the highest torque ratings. The towing capacity is 12,100 pounds (when properly equipped), and the maximum payload measures 1,840 pounds. By comparison, the most powerful engine offering, a 3.5-liter twin-turbo gasoline V-6, is more potent with 400 hp and 500 lb.-ft. of torque. However, the torque comes at 3,100 rpm — building twice as slowly as the diesel's torque.

Moving up a rung on the Ford truck ladder, the Super Duty equipped with the optional 6.7-liter turbodiesel V-8 generates 475 hp at 2,600 rpm and a class-leading 1,050 lb.-ft. torque beginning at 1,600 rpm. Towing is rated at 15,000 pounds with a payload of 2,462. That's the minimum tow rating, mind you, as the heavy-duty F-450 can tow 37,000 pounds with a gooseneck or 5th-wheel hitch.

How Torque Works in a Turbocharged Engine

Turbocharging and supercharging also affect torque because peak power occurs over a wider rpm range rather than a specific point on the torque bell curve.

Consider the 2020 Honda Accord. Its standard turbocharged 1.5-liter inline 4-cylinder engine is small for this car's size, but it produces 192 hp at 5,500 rpm and delivers 192 lb-ft. of torque between 1,600-5,000 rpm. The Accord's optional 2.0-liter turbo-four offers 252 hp at 6,500 rpm and peak torque of 273 lb.-ft. from 1,500-4,000 rpm. When peak torque spreads across a wide rev range like this, it produces rapid acceleration and the satisfying thrust you feel as you're pushed back into your seat.

In theory, turbocharging and supercharging allow automakers to use smaller, more fuel-efficient engines in their vehicles. However, the harder you drive one out in the real world, the less noticeable the fuel economy benefit.

How Torque Works in an Electric Vehicle

With electric vehicles (EVs), power comes from electric motors. With no engine to crank, peak torque arrives instantaneously. This is why EVs like the Tesla Model 3, which doesn't officially list horsepower or torque figures, can boast a zero-to-60 mph time of 3.2 seconds. (For the record, according to Motor Trend, this dual-motor Performance all-wheel-drive model delivers 450 hp and 471 lb.-ft. of immediate torque).

Even EVs considered low in terms of power are still quick off the mark and serve as exuberant stop-and-go commuter vehicles. The Chevrolet Bolt EV makes 200 hp, but with 266 lb.-ft. of torque at zero rpm it is a quick little car. Likewise, the Kia Niro EV offers 201 hp and delivers on-demand torque of 291 lb.-ft. for plenty of scoot.

This same benefit applies to hybrids, too, which pair an electric motor with an ICE. The quick torque delivery from a hybrid's electric assist motor propels the vehicle at lower speeds. A Toyota Prius is a good example here. While the Prius is rated to make a meager 121 horsepower, its electric assist motor delivers 120 lb.-ft. of torque the moment the driver presses on the accelerator pedal.