Plymouth Road Runner Power Gains: Comparing High-flow Heads, Camshaft Upgrades, and Intake Systems

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The Plymouth Road Runner is a classic muscle car that has captured the hearts of automotive enthusiasts since its debut in the late 1960s. One of the most exciting aspects of owning a Road Runner is the potential for power gains through various modifications. This article will explore the impact of high-flow heads, camshaft upgrades, and intake systems on the performance of the Plymouth Road Runner.

Understanding the Basics of Engine Performance

Before diving into specific upgrades, it’s essential to understand the fundamentals of engine performance. The power output of an engine is determined by several factors, including air intake, fuel delivery, and exhaust flow. Improving any of these areas can lead to significant gains in horsepower and torque.

High-Flow Cylinder Heads

High-flow cylinder heads are one of the most effective ways to increase engine performance. These heads are designed to improve airflow, allowing the engine to breathe better and produce more power. Here are some key points to consider:

  • Increased Airflow: High-flow heads reduce restrictions in the intake and exhaust ports, which enhances airflow.
  • Better Combustion: Improved airflow leads to more efficient combustion, resulting in higher power output.
  • Compatibility: Ensure that the heads are compatible with your engine’s specifications and other modifications.

Several aftermarket companies offer high-flow cylinder heads specifically designed for the Plymouth Road Runner. Some popular options include:

  • Edelbrock Performer RPM Heads: Known for their excellent airflow characteristics and performance gains.
  • Indy Cylinder Heads: Offers a range of high-performance heads that cater to various performance needs.
  • World Products: Provides affordable options that still deliver impressive performance increases.

Camshaft Upgrades

The camshaft plays a crucial role in determining the engine’s performance characteristics. Upgrading to a performance camshaft can significantly enhance power output by optimizing the timing and duration of valve openings. Here are some considerations when selecting a camshaft:

  • Duration and Lift: A camshaft with higher duration and lift can improve airflow and increase horsepower.
  • Idle Characteristics: Consider how the camshaft will affect idle quality and drivability.
  • Power Band: Choose a camshaft that complements your engine’s power band for optimal performance.

When selecting a camshaft for your Plymouth Road Runner, consider these popular options:

  • Comp Cams Xtreme Energy: Offers a wide power band and excellent throttle response.
  • Lunati Voodoo: Known for its aggressive profile and strong mid-range power.
  • Crane Cams: Provides a variety of performance camshafts tailored for different engine setups.

Intake Systems

The intake system is vital for delivering air to the engine. Upgrading to a high-performance intake manifold can enhance airflow and improve overall engine performance. Here are some factors to consider when upgrading your intake system:

  • Manifold Design: Choose a design that matches your engine’s performance goals, whether for street or racing applications.
  • Throttle Body Size: Larger throttle bodies can increase airflow but may require tuning for optimal performance.
  • Material: Consider the material of the intake manifold, as it can affect weight and heat dissipation.

Top Intake System Choices for the Road Runner

Here are some highly recommended intake systems for enhancing the performance of your Plymouth Road Runner:

  • Edelbrock Performer Intake: A popular choice for street applications, offering a good balance of performance and drivability.
  • Holley Strip Dominator: Designed for high-performance applications, maximizing airflow for racing conditions.
  • Weiand Stealth Intake: Known for its versatility and excellent performance across a range of RPMs.

Combining Upgrades for Maximum Gains

To achieve the best performance gains, it’s essential to consider how these upgrades work together. Combining high-flow heads, a performance camshaft, and an optimized intake system can lead to significant improvements in horsepower and torque. Here are some tips for successful integration:

  • Tuning: After making upgrades, ensure proper tuning of the engine to maximize performance and efficiency.
  • Supporting Mods: Consider additional modifications, such as exhaust upgrades, to complement your performance enhancements.
  • Testing: Dyno testing can help you understand the impact of your modifications and refine your setup.

Conclusion

Upgrading the Plymouth Road Runner with high-flow heads, camshaft upgrades, and intake systems can lead to impressive power gains. By understanding the fundamentals of engine performance and choosing the right components, you can transform your Road Runner into a high-performance machine. Whether you’re a casual driver or a racing enthusiast, these upgrades will enhance your driving experience and ensure that your Road Runner remains a classic icon of American muscle.