How Much Horsepower Does a Plenum Spacer Add?

Plenum spacers have long been a topic of interest for automotive enthusiasts seeking to enhance their vehicle's performance. These unassuming components, often overlooked in the grand scheme of engine modifications, have shown a remarkable ability to unlock additional horsepower and torque. By increasing the volume of air entering the intake plenum, these spacers effectively improve the engine's breathing capabilities, resulting in a noticeable boost in power. Among the various methods of achieving this, adding a spacer to the intake plenum has emerged as an efficient and reliable option. Extensive dyno testing has revealed that certain intake plenum spacers can deliver up to an impressive 14 horsepower gain, providing a significant enhancement to overall engine performance.

How Much HP Does a Plenum Spacer Add to a G35?

The Motordyne Copper Iso Thermal plenum spacer is a highly sought-after upgrade for G35 enthusiasts looking to enhance the performance of their vehicles. Offering a unique blend of power gains and heat management, this modification is known to add approximately 12 to 14 horsepower to the engine output of the G35.

Designed to tackle power-robbing heat soak, the plenum spacer effectively thermally isolates both the upper and lower plenum. By introducing a copper isothermal material between these components, it minimizes the transfer of heat, subsequently reducing the negative impact on engine performance. This innovative design ensures that the engine can maintain optimal operating temperatures, resulting in improved power output.

The benefits of the Motordyne Copper Iso Thermal plenum spacer don’t stop at horsepower gains. Additionally, it positively affects torque delivery, providing drivers with a more responsive throttle and improved overall drivability. The enhanced power and torque can be felt across the entire power band, allowing for a thrilling driving experience.

The installation of the plenum spacer is a straightforward process, generally requiring basic hand tools and some mechanical know-how. It’s crucial to ensure proper fitment to guarantee effective thermal isolation and maximize performance gains. Therefore, following the manufacturers installation instructions and recommendations is highly recommended.

It’s unique design and high-quality materials make it a popular choice among enthusiasts looking to unlock the true potential of their G35s engine.

The Potential Impact of the Plenum Spacer on Engine Sound and Exhaust Note.

  • The plenum spacer can enhance the engine sound and exhaust note.
  • It can make the engine sound deeper and more aggressive.
  • The spacer creates more airspace in the plenum chamber, allowing for better airflow.
  • This improved airflow can contribute to a louder and more distinct exhaust note.
  • Some enthusiasts install plenum spacers for the sole purpose of enhancing the engine sound.
  • However, it’s important to note that the impact of a plenum spacer on engine sound can vary depending on other modifications and the specific vehicle.
  • It’s always recommended to consult with a professional or experienced individuals before installing a plenum spacer.

Plenum spacers offer a simple yet effective solution to enhance the performance of a vehicle’s engine. By fitting the spacer between the upper sections of the plenum, the intake manifold’s size and volume are increased, allowing for an improved airflow and ultimately more power.

What Is the Benefit of Plenum Spacer?

The plenum spacer serves as a simple yet effective modification for engine enthusiasts looking to enhance the performance of their vehicles. By installing the spacer between the upper 2-piece section of the Plenum, it enlarges the size of the Intake Manifold, which in turn increases the volume of air that can be drawn into the engine during the intake stroke.

As the saying goes, “more air, more power.”. With greater airflow, the engine can efficiently burn fuel and generate more power. This results in improved throttle response, increased horsepower, and enhanced overall performance.

A larger plenum volume allows for improved air distribution among the cylinders, ensuring a more even and consistent air-to-fuel ratio. This leads to smoother engine operation, reduced hesitation, and minimized engine fluctuations. Additionally, the increased intake volume can also lower intake air temperatures, resulting in cooler and denser air entering the engine, further improving combustion efficiency.

It’s a relatively simple and non-intrusive upgrade that can deliver noticeable improvements in engine performance. It’s a popular choice for enthusiasts seeking to maximize the potential of their engines without extensive modifications or tuning.

It’s a desirable modification for engine enthusiasts looking to unlock the true potential of their vehicles, and a relatively straightforward procedure for those seeking noticeable performance gains.

One simple modification that can enhance the performance of an engine is the addition of a spacer. While this alteration may seem insignificant, it serves to increase the capacity within the intake manifold, accommodating a greater volume of air. As a result, the engine benefits from improved combustion reactions, leading to a noticeable boost in both horsepower and torque.

Does Spacer Add HP?

Does a spacer add horsepower (HP)? This is a common question among car enthusiasts looking to boost their engine performance. While the addition of a spacer may not bring about a drastic change to the engine setup, it does have it’s effects. One significant benefit of using a spacer is that it provides extra room for air to enter the intake manifold.

However, even a marginal increase in horsepower can make a noticeable difference in the performance of your vehicle.

The extent of these gains will vary depending on several factors, but even a slight increase can enhance the overall performance of your vehicle.

Potential Drawbacks or Risks: Alongside the Benefits, It Is Important to Highlight Any Potential Drawbacks or Risks Associated With Using Spacers. This Could Include Issues Such as Decreased Low-End Torque, Potential Compatibility Issues With Certain Engine Designs, or the Possibility of Voiding Warranties. Providing a Balanced View Will Enable Readers to Make an Informed Decision.

  • Decreased low-end torque
  • Potential compatibility issues with certain engine designs
  • Possibility of voiding warranties

Source: How much horsepower does a throttle body spacer add?..

By raising the plenum, the angled aluminum plenum spacer for the 350Z – G35 VQ35DE allows for increased airflow to the front cylinders, all while allowing the retention of the factory strut tower brace. This specially designed spacer aims to enhance engine performance by optimizing air intake and combustion efficiency.

What Does a Plenum Spacer Do G35?

A plenum spacer for the G35 is an angled aluminum component that serves a specific purpose. It’s designed to enhance the airflow to the engine of the 350Z or G35 VQ35DE, while simultaneously enabling the retention of the factory strut tower brace. By raising the plenum, it enables increased air flow specifically to the front cylinders.

The increase in airflow provided by the plenum spacer is crucial for optimizing engine performance. As air is a fundamental requirement for combustion, an improved air supply translates into enhanced power delivery. With increased airflow to the front cylinders, the engine can operate more efficiently, ultimately leading to improved performance and potential power gains.

This can reduce the likelihood of air turbulence or restrictions, promoting more consistent fuel combustion and overall engine operation. By facilitating the efficient mixing of fuel and air, it can contribute to better fuel economy and potentially even a slightly leaner air-to-fuel ratio.

Furthermore, the installation of a plenum spacer is relatively straightforward and can be done without major modifications to the engine. This allows enthusiasts to enhance their engines performance without sacrificing the factory strut tower brace, which plays a crucial role in maintaining chassis rigidity and stability.

How a Plenum Spacer Affects Engine Performance

A plenum spacer is a device that’s installed between the intake manifold and the throttle body in an engine. It’s typically used to increase the volume of the plenum chamber, which allows for better airflow and can potentially improve engine performance. By increasing the plenum volume, a plenum spacer can help enhance air intake and distribution, which may result in improved power, torque, and throttle response. Additionally, the spacer can create a better environment for air and fuel mixing, leading to more efficient combustion. Overall, a plenum spacer can have a positive impact on engine performance by optimizing airflow and fuel combustion.

Plenum spacers come in various thicknesses such as 5/16″, 1/2″, and 5/8″. These spacers are designed to increase the plenum volume and improve the airflow in the intake manifold. By installing a plenum spacer, enthusiasts hope to enhance their vehicle’s performance and achieve a noticeable difference in power and throttle response. Now let’s take a closer look at the benefits and considerations of each spacer thickness.

What Size Are Plenum Spacers?

When it comes to plenum spacers, size matters. These spacers come in various dimensions to suit different vehicles and their specific requirements. Plenum spacer thickness can range from 5/16 inch to 5/8 inch, with the options of 1/2 inch also available.

The thickness of the plenum spacer can have a significant impact on it’s performance. On the other hand, a thinner spacer may offer a more subtle effect on the engine, providing a balance between improved performance and minimal interference with the stock setup.

The shape, design, and material of the spacer also play an essential role. Engineers and enthusiasts should consider all these factors collectively to select the ideal plenum spacer that best suits their individual needs and goals.

The thickness of the spacer affects the airflow and performance of the engine.

Examples of Vehicles That Can Benefit From Using a Plenum Spacer

  • Cars
  • Trucks
  • SUVs
  • Vans
  • Motorcycles
  • ATVs
  • RVs
  • Boats
  • Jet skis
  • Golf carts


The results have shown that these modifications can yield significant gains, with gains of up to 14 BHP being observed in real-world scenarios.

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