Horsepower Inc. Max Flow™ 55 mm Throttle Body for Harley-Davidson Twin Cam Engines

Boost your Harley-Davidson® Twin Cam performance with the HPI Max Flow™ Throttle Body – 55 mm, engineered for superior airflow, throttle response, and top-end power. Designed as a direct replacement for your OEM throttle body and manifold, this unit offers exceptional precision, durability, and compatibility with all factory components.

Crafted from CNC-machined billet aluminum, each throttle body is internally ported and polished for maximum flow efficiency. The sealed double roller bearing ensures smooth, reliable throttle movement, while the large plenum designenhances air delivery for high-output builds.

Whether you’re upgrading a stock engine or tuning a big-bore Twin Cam, the Max Flow™ 55 mm delivers consistent performance gains with the quality and reliability riders expect from Horsepower Inc.

Key Features

• Direct OEM Replacement: Replaces the stock throttle body and manifold with no additional modifications.

• Precision Machined: CNC-cut from billet aluminum and internally ported for optimal airflow.

• Improved Performance: Ideal for high-displacement Twin Cam motors that demand more air volume.

• Smooth Operation: Equipped with sealed double roller bearings for precise throttle response.

• Enhanced Airflow Design: Large plenum construction boosts mid- to high-RPM horsepower.

• Made in the USA: Built by performance experts with premium materials and craftsmanship.

Fitment – Harley-Davidson Twin Cam Models

Fits the following Harley-Davidson® Twin Cam models (2001–2005):

Touring Models:

• FLTRI Road Glide (2002–2005)

• FLHRI Road King (2002–2005)

• FLHRCI Road King Classic (2002–2005)

• FLHTI Electra Glide Standard (2003–2005)

• FLHTCI Electra Glide Classic (2002–2005)

• FLHTCUI Electra Glide Ultra Classic (2002–2005)

Softail Models:

• FLSTFI Fat Boy (2002–2005)

• FLSTNI Softail Deluxe (2005)

• FLSTCI Heritage Softail Classic (2001–2005)

• FXSTI Softail Standard (2001–2005)

• FXSTDI Softail Deuce (2001–2005)

• FXSTBI Night Train (2001–2005)

• FXSTSI Springer Softail (2001–2005)

• FLSTSI Heritage Springer (2001–2003)

Dyna Models:

• FXDI Dyna Super Glide (2004–2005)

• FXDLI Dyna Low Rider (2004–2005)

• FXDXI Dyna Super Glide Sport (2004–2005)

• FXDWGI Dyna Wide Glide (2004–2005)

• FXDCI Super Glide Custom (2005)

Fitment based on stock configurations. Not legal for sale or use in California on pollution-controlled vehicles.

Technical Specifications

• Product Name: Throttle Body

• Model: Max Flow™

• Type: Single Bore

• Bore Size: 55 mm

• Material: Billet Aluminum

• Color/Finish: Black Anodized

• Features: Internally Ported / 1.80" Intake Runner / Sealed Roller Bearing

• Compatibility: Twin Cam Engines (2001–2005)

• Units: Each

• Riding Style: Street / Performance / Touring

• Made in: USA