What is a Hemi eTorque Engine and What Makes It Special?

Lisa Conant, Automotive Features Reviewer at CarParts.com

Reviewed by

Lisa Conant, Automotive Content Specialist

Automotive Features Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on January 23rd, 2024

Reading Time: 4 minutes
Summary
  • The Hemi eTorque is a hybrid engine in RAM vehicles that combines efficient hemispherically shaped combustion chambers and hybrid technology.
  • eTorque engines replace the alternator with a 48-volt battery-powered belt drive and a motor generator that provides extra torque.
  • Hemi eTorque engines can power themselves by burning fuel and recapturing energy from the vehicle’s inertia during deceleration to power electrical systems.
  • The advantages of a Hemi eTorque engine include excellent fuel economy, improved towing capabilities, and better quality of life.
  • The drawbacks of a Hemi eTorque engine are higher maintenance costs, increased emissions, and potential engine problems.

Commonly found in RAM, Dodge, and Chrysler vehicles, Hemi engines are optimized to burn the least amount of fuel to generate the most power possible.

RAM came up with a special engine: the Hemi eTorque, which incorporates hybrid tech that lets the vehicle partially power itself. It accomplishes this feat by converting the captured energy from the braking system into electricity for the battery pack, which is then used to power all sorts of electrical components.

If you want to learn more about Hemi eTorque engines, how they work, and what makes them unique, read on.

What Is the Hemi eTorque Engine?

The Hemi eTorque is a special engine in RAM vehicles. They’re durable, long-lasting, and incredibly fuel-efficient.

The “Hemi” of the Hemi eTorque engine gets its name from its hemispherically-shaped combustion chambers. Its unique shape isn’t just for show, as hemispherical combustion chambers are larger and have a dome-shaped cylindrical head.

The unique shape means they have significantly more room for combustion, all while improving airflow to maximize power and torque generation per ounce of fuel burned up.

Meanwhile, “eTorque” refers to a type of hybrid technology that’s designed to improve the vehicle’s fuel economy without sacrificing power. During deceleration, it captures energy from the vehicle’s inertia and converts it to electrical energy for later use.

What Does an eTorque Engine Do?

eTorque engines replace the alternator with a 48-volt battery-powered belt drive and a motor generator. With this setup, the engine can reach higher levels of performance, power, and efficiency.

The motor generator provides extra torque to the crankshaft during gear changes, minimizing both noise and vibration in the engine. Simultaneously, the motor generator uses the 48-volt battery pack to increase torque even further, delivering a power boost to help with acceleration and towing.

Hemi eTorque engines can typically be found in Dodge, Chrysler, RAM, and Jeep vehicles.

How Does the Hemi eTorque Work?

Hemi eTorque engines have a unique electrical system that enables the motor generator to supply electricity to the vehicle’s battery pack, charging it whenever the engine is running. 

They have a mild hybrid setup wherein the battery pack and motor generator perform several functions on top of the functions of a regular alternator. 

For example, eTorque engines can recapture energy whenever the vehicle decelerates to further charge the battery. This boosts fuel economy and overall drivability. 

In short, the Hemi eTorque has two ways of powering itself: burning up fuel and using the energy harnessed through regenerative braking.

Advantages of Hemi eTorque

Let’s look into some of the reasons why Hemi eTorque engines are in demand.

Excellent Fuel Economy

The Hemi eTorque engine doesn’t need to burn as much fuel as other engines to generate tremendous power.

Its excellent fuel mileage also means that you can expect to save a lot of money on gas. This is in part thanks to the Hemi engine’s hemispherical combustion chambers, which maximize the power generated when fuel combusts.

The Hemi eTorque engine’s regenerative braking also contributes to better fuel economy.

Improved Towing Capabilities

Increased power means increased towing capabilities. In other words, vehicles with Hemi eTorque engines will have a much easier time driving around with trailers or towing platforms.

This capability makes vehicles with this engine excellent “beasts of burden.” If you’re moving houses or if you need to deliver something heavy without hiring a delivery truck, your vehicle can get the job done if it has a Hemi eTorque engine.

Quality of Life

Last but not least, Hemi eTorque engines make vehicles infinitely easier to drive, thanks to their ability to recapture energy. After all, the battery pack can charge itself whenever you use the brakes.

Moreover, Hemi eTorque engines also minimize noise and vibration whenever you drive, making for smooth and satisfying driving experiences. They also start and stop smoothly and with little-to-no complications.

The added power from the hybrid setup allows torque to reach the wheels within 400 milliseconds, making it twice as fast as the average engine and startup battery.

Disadvantages of Hemi eTorque

Despite the many benefits that vehicles with Hemi eTorque engines have to offer, they’re not perfect. Here are their drawbacks:

Increased Maintenance Costs

Maintaining the Hemi eTorque engine can get expensive. You’ll need to take regular care of both the unique hemispherical combustion chamber and the electrical components, like the 48-volt battery-powered belt drive.

The engine itself also costs a lot more than your run-of-the-mill engine, with prices well over $5000.

Drivers of vehicles with Hemi eTorque engines have also complained about having to get their car battery packs replaced often because they see more use than the average vehicle. The cost of repairs and part replacements can rack up over time.

Increased Emissions

Although Hemi eTorque engines maximize the power generated relative to the amount of fuel consumed, they also produce toxic nitrogen oxide gases. Fortunately, catalytic converters and exhaust gas recirculation can mitigate this problem.

Engine Problems

Because of its unique design, and because it’s optimized for fuel efficiency, the Hemi eTorque engine doesn’t handle specific inconveniences as well as other engines do.

For example, Hemi eTorque engines need to use high-octane fuel to maintain their performance. They’re also prone to timing problems and low fuel levels. This means you have to work harder to keep your engine in tip-top shape.

In addition, a lot of problems come with the Hemi eTorque engine’s size. Because of its large and hemispherical combustion chamber, the Hemi engine leaves little room in the engine for anything else.

About The Authors
Reviewed By Lisa Conant

Automotive Features Reviewer at CarParts.com

Lisa Conant grew up in Canada around a solid contingency of gear heads and DIY motor enthusiasts. She is an eclectic writer with a varied repertoire in the automotive industry, including research pieces with a focus on daily drivers and recreational vehicles. Lisa has written for Car Bibles and The Drive.

Written By CarParts.com Research Team

Automotive and Tech Writers

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