Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

Optimize performance from your Stage IV equipped Milwaukee-Eight powertrain by bolting on this Screamin’ Eagle Extreme Flow 64MM EFI Intake Manifold. Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

• Cast aluminum body and CNC ported intake runners provide smooth, undisturbed air intake you need for maximum power output

• Delivers a 2% – 4% horsepower increase you’ll notice every time you twist the throttle

• Updated calibrations make installation and tuning easy

• All models require ECM calibration with Screamin’ Eagle® Pro Street Tuner for proper installation

Fits ’18-later Softail, and ’17-later Touring (except ’23-later FLHXSE, FLTRXSE, ’24-later FLHX and FLTRX) models equipped with Screamin’ Eagle® Milwaukee-Eight Stage IV kits. All models require ECM calibration with Screamin’ Eagle Pro Street Tuner or dealership installed Screamin’ Eagle calibration for proper installation. Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

The Screamin’ Eagle Extreme Flow 64 mm EFI Intake Manifold (Part #27300185) is a performance-oriented induction upgrade engineered by Harley-Davidson’s Screamin’ Eagle division to enhance the airflow characteristics of Stage IV–equipped Milwaukee-Eight engines. Designed as a direct replacement for the stock intake manifold on compatible Softail and Touring models, this component merges high-quality construction with precision porting to help unlock additional power across the engine’s rev range while maintaining strong reliability and street-legal compliance.(Harley-Davidson) Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

At its core, this intake manifold is crafted from a robust cast aluminum body that offers excellent strength and thermal resistance. Aluminum construction not only keeps weight down but also holds up well in the high-temperature environment typical of a performance engine’s air intake path. The defining feature of this manifold is its CNC-ported intake runners—machined pathways that minimize airflow disruptions and promote smooth, consistent air delivery into the engine. By reducing turbulence and increasing flow efficiency, the Extreme Flow manifold helps the engine inhale more air with less restriction, which is a fundamental requirement for improved combustion and performance.(Harley-Davidson) Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

While performance gains can vary based on the complete setup, Harley-Davidson states that the Extreme Flow 64 mm manifold can provide a noticeable 2 % to 4 % increase in horsepower—an improvement riders can feel as stronger throttle response and more vigorous acceleration. This gain is particularly meaningful in a Stage IV build, where supporting mods like high-flow air cleaners, performance cams, and enhanced exhaust systems combine to elevate power well beyond stock levels. The manifold works in concert with these components and is designed to complement the overall Stage IV strategy.(Harley-Davidson) Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

Installation of this intake manifold requires proper tuning. Harley-Davidson specifies that all models equipped with this part must be calibrated using the Screamin’ Eagle Pro Street Tuner or have corresponding dealer-installed calibration performed for correct operation. This is crucial because alterations to airflow characteristics directly affect fuel delivery and engine management parameters; without proper calibration, drivability and performance gains may not be fully realized. In some regions, this intake manifold is 50-state U.S. EPA compliant, meaning it meets emissions regulations in all states except for specific exceptions pending approval—which is often the case for performance parts.(Harley-Davidson) Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

Compatibility for the Extreme Flow 64 mm manifold covers a wide range of Harley-Davidson motorcycles, including ‘18–’25 Softail and ‘17–’25 Touring models equipped with Milwaukee-Eight engines running Stage IV performance kits. There are though exclusions for certain late-model variants such as some FLHXSE, FLTRXSE, and newer FLHX and FLTRX versions, so verifying fitment with your specific bike is recommended before purchasing or installing.(Harley-Davidson) Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185

Beyond performance, the manifold contributes to a cleaner look within the engine bay thanks to its streamlined design. Riders who invest in cosmetic and performance upgrades alike appreciate parts that enhance both function and appearance. Whether installed alone or as part of a comprehensive performance package, this manifold helps deliver stronger engine performance with the quality and reliability expected from genuine Harley-Davidson Screamin’ Eagle components.(Harley-Davidson) Harley-Davidson Screamin’Eagle Extreme Flow 64mm EFI Intake Manifold 27300185