Connect with us


Flywheel vs Flexplate: Understanding the Differences




When it comes to the powertrain of an automobile, the flywheel and flexplate are two essential components that play a crucial role in transmitting power from the engine to the wheels. While both serve similar purposes, there are significant differences between them that can impact performance and efficiency.

A flywheel is a mechanical device that stores rotational energy. It is typically attached to the engine’s crankshaft and serves as a weighty component that helps smooth out any fluctuations in engine speed caused by combustion cycles. This reduces vibration and provides greater stability for smoother operation.

Flexplates, on the other hand, are designed specifically for automatic transmissions. They perform essentially the same function as flywheels but with some important distinctions. Unlike flywheels which connect directly to manual transmissions via a clutch system, flexplates attach to torque converters found in automatic transmission systems.

Another key difference between these two components lies in their construction materials. Flywheels tend to be made of steel or aluminum while flexplates are primarily composed of thin sheets of metal such as stamped steel or cast iron.

Additionally, because they serve different types of engines (manual vs automatic), they differ significantly in size and shape too – with flywheels being substantially larger than their counterparts due mainly due to their direct connection with manual gearboxes.

Ultimately, whether you choose a flywheel or flexplate depends on your specific needs based on your vehicle type along with driving style preferences – so make sure you consult with professionals who can advise you accordingly!

Flywheel vs Flexplate: What are they?

Both flywheels and flexplates are essential components of an internal combustion engine, but they serve different purposes. A flywheel is a mechanical device that stores rotational energy and helps to smooth out the power delivery from the engine. On the other hand, a flexplate serves as a connection between the engine and transmission in an automatic transmission vehicle.

A flywheel is typically found on manual transmission vehicles, where it serves several functions. Firstly, it acts as a mounting surface for the clutch assembly. Secondly, it stores kinetic energy generated by the engine during its operation, which helps to maintain consistent rotational speed when there are fluctuations in torque output from the crankshaft. This allows for smoother gear changes and prevents stalling at low speeds or when starting off.

A flexplate is similar to a flywheel in appearance but has some key differences. It’s found exclusively on automatic transmission vehicles and connects directly to the torque converter housing within the transmission bell housing. The primary function of a flexplate is to transmit torque from the engine to the transmission while also allowing for some flexibility due to its design.

The reason for this flexibility is that an automatic transmission needs some degree of movement between itself and its mating components due to variations in temperature expansion, vibration dampening or misalignment issues that may arise during normal use over time.

In summary, both flywheels and flexplates play crucial roles in ensuring proper operation of an internal combustion engine – whether manual or automatic transmissions – by smoothing power delivery or serving as connectors between vital components respectively.

The Function of Flywheels and Flexplates

Flywheels and flexplates are essential components in the operation of internal combustion engines. They serve different but equally important functions that ensure smooth engine performance.

A flywheel is a heavy disc-shaped component that is attached to the crankshaft of an engine. Its primary function is to store rotational energy produced by the engine during its power stroke and release it during the non-power strokes, which helps maintain a consistent speed for the crankshaft. The stored energy also provides additional torque when starting the engine or accelerating from a stop. In addition, flywheels help reduce vibrations caused by uneven combustion cycles, contributing to smoother running engines.

On the other hand, flexplates perform a similar function as flywheels in automatic transmissions. However, they have some distinct differences due to their application in automatic transmissions. Unlike flywheels which are bolted directly onto manual transmission clutches, flexplates connect to torque converters using bolts or rivets.

Flexplates also have more teeth around their circumference compared to flywheels since they need these teeth for engagement with starters and transmission gears. Additionally, flexplates are made from thinner materials such as stamped steel or aluminum because they do not require as much mass as flywheels.

Both components play critical roles in ensuring smooth engine performance regardless of whether you use a manual or automatic transmission vehicle.

In conclusion, while both components serve similar purposes in storing rotational energy produced by an internal combustion engine, they differ significantly depending on their application within either manual or automatic transmissions systems respectively. Understanding how each component works will help drivers appreciate how crucial they are towards maintaining optimal vehicle performance levels over time while preventing damage caused by excessive vibration or wear and tear on critical parts like bearings etcetera

Flywheel vs Flexplate: Key Differences

When it comes to the engine of a vehicle, there are many components that work together to ensure smooth and efficient operation. Two such components are the flywheel and flexplate. While they may seem similar at first glance, these parts have important differences that affect their performance and usage.

What is a Flywheel?

A flywheel is a mechanical device used in engines to store rotational energy. It’s typically made of cast iron or steel and mounted on the end of the crankshaft. The primary function of a flywheel is to smooth out any fluctuations in engine speed caused by uneven power delivery from pistons or other sources.

In addition, a flywheel also helps start an engine by storing enough energy during cranking to keep it running for several revolutions until fuel combustion takes over.

What is a Flexplate?

A flexplate serves essentially the same purpose as a flywheel but is used specifically in automatic transmission vehicles rather than manual ones. It’s located between the torque converter and transmission input shaft and is attached directly to the crankshaft via bolts or dowel pins.

The main difference between a flexplate and flywheel lies in its design; whereas flywheels have teeth around their perimeter for engaging with starter motors, flexplates have smaller openings through which torque converters can attach themselves.

Differences Between Flywheels & Flexplates

  • Material: Flywheels tend to be made from heavier materials like cast iron or steel while flexplates are often constructed using lighter metals such as aluminum or composite materials like carbon fiber.
  • Type of Transmission: As mentioned earlier, one significant difference between these two components is their application. Flywheels are typically used in manual transmission vehicles, while flexplates are found in automatic ones.
  • Size: Generally speaking, flywheels tend to be larger and heavier than flexplates due to the extra demands placed on them by manual transmissions. Conversely, flexplates can afford to be lighter and smaller since they’re not dealing with as much torque or rotational force.
  • Tooth Count: Flywheels have teeth around their perimeter for engaging with starter motors whereas a flexplate has openings through which torque converters can attach themselves.

In conclusion, both flywheels and flexplates play vital roles in engine operation but differ significantly in terms of design and usage. Understanding these differences is essential when choosing the right component for your vehicle’s specific needs.

Advantages and Disadvantages of Flywheels and Flexplates

Flywheels and flexplates both play an important role in the operation of a vehicle’s engine. While they have some similarities, there are also distinct differences between them that make each better suited for certain applications.

Flywheel Advantages:

  • Greater energy storage capacity: Flywheels can store more energy than flexplates due to their heavier weight, making them ideal for high-performance engines.
  • Better clutch engagement: The added weight of a flywheel helps provide smoother clutch engagement, resulting in less wear on the clutch itself.
  • Designed for manual transmissions: Flywheels are typically used with manual transmissions as they help maintain momentum during gear changes, resulting in smoother shifting.

Flywheel Disadvantages:

  • Heavier weight: While the added weight is beneficial for performance reasons, it can also lead to increased fuel consumption due to the extra work required by the engine to rotate it.
  • Incompatible with automatic transmissions: Due to their design and heavy weight, flywheels are not compatible with automatic transmissions which require a flexplate instead.

Flexplate Advantages:

  • Lowers overall vehicle weight: Flexplates are significantly lighter than flywheels which helps reduce overall vehicle weight leading to improved fuel economy. Ideal for automatic transmission systems – As previously mentioned, Automatic transmission systems require flex plates because they need something lightweight enough that will allow easy rotation but strong enough to handle torque from the engine without breaking or cracking over time.

Flexplate Disadvantages:

  • Less energy storage capacity: Flexplates have less energy storage capacity than flywheels due to their lighter weight, making them less suitable for high-performance engines.
  • Poor clutch engagement: Since flexplates are lightweight, they do not provide the same level of momentum as a flywheel during gear changes resulting in rougher shifting and more wear on the transmission.

    In conclusion, both flywheels and flexplates have their advantages and disadvantages depending on the specific needs of your vehicle. If you have a manual transmission or require higher performance capabilities, then a flywheel may be the better option. However, if you have an automatic transmission or are looking to improve fuel economy by reducing overall weight, then a flexplate is likely the way to go.

    Which One to Choose: Flywheel or Flexplate?

    When it comes to choosing between a flywheel and a flexplate, there are several factors that you need to consider. Both of these components serve the same purpose, which is to transfer power from the engine to the transmission. However, they are designed differently and have their own unique advantages and disadvantages.


    A flywheel is a disc-shaped component that is bolted directly onto the crankshaft of an engine. It serves as a mounting surface for the clutch assembly and provides rotational inertia for smooth operation of the engine. A flywheel also helps in maintaining consistent RPMs while shifting gears.

    The advantage of using a flywheel is that it can handle high horsepower applications better than flexplates due to its heavier weight and ability to absorb more shock loads. This makes it ideal for racing applications where quick acceleration and deceleration are required.


    A flexplate, on the other hand, looks similar but has some key differences from a flywheel. It is thinner than a flywheel and uses an automatic transmission torque converter instead of a clutch assembly for power transfer. The flexibility in its design allows it to bend slightly under load without breaking.

    The main advantage of using a flexplate over a flywheel is its lighter weight which results in faster acceleration and improved fuel economy. Its design also allows easier installation since there’s no need for alignment with clutch assembly or pilot bearing.


    In summary, both components have their own strengths depending on your specific needs such as performance level, type of transmission being used etcetera . If you’re looking at building an engine with high horsepower output then go with Flywheels whereas if you want something lightweight yet efficient for daily driving, then Flexplates are a better choice.

    Ultimately, it is important to choose the right component that best suits your needs and provides optimal performance.


    After comparing the flywheel and flexplate, it can be concluded that both have their unique advantages and disadvantages. The choice between the two largely depends on the intended use of the vehicle.

    If you are looking for a smooth and quiet ride, then a flexplate is your best bet. It also provides better fuel efficiency due to its lightweight design. On the other hand, if you prioritize power and performance, then a flywheel is what you need. Its heavier weight allows for more torque transfer to the wheels, making it ideal for high-performance vehicles.

    It’s important to note that when replacing either component in your vehicle, it’s crucial to choose one that matches your engine type and transmission setup. Using an incompatible flywheel or flexplate can result in serious damage to your engine or transmission.

    Overall, understanding the differences between flywheels and flexplates is essential when building or modifying a vehicle. By choosing the right component based on your driving needs and mechanical requirements, you’ll ensure optimal performance from your car or truck while avoiding costly repairs down the road.

Click to comment

Leave a Reply

Your email address will not be published. Required fields are marked *

Recent comments

About us is an online resource with guides & diagrams for all kinds of vehicles. If you look for a fuse box diagram, timing belt diagram, or maybe wiring diagram – this is a place for you. We also have over 350 guides & DIY articles about cars.


Copyright © 2015-2023