Airaid PowerAid Throttle Body Spacer for 1997-2003 Ford F-150 and 1997-2004 Expedition 5.4L, AIR400-591

The POWERAID Throttle Body Spacer is designed to enhance off-idle torque from 800 rpm to approximately 3,000 rpm. The spacer utilizes it's unique, patented Helix Bore design to spin the incoming air charge as it passes through the throttle body spacer. The spinning air action boosts the velocity of the incoming air and contributes to better atomization of the air/fuel mixture as the air charge enters the combustion chamber. The end result is more part-throttle torque and improved mid-range power. The POWERAID Throttle Body Spacer is designed to enhance mid-range torque using a patented Helix Bore which spins intake air going through the throttle body spacer. Mounting hardware included for installation.

• True bolt-on upgrade that installs in under an hour with common hand tools. No drilling, cutting, or modifications required, making it one of the easiest performance add-ons you can install.
• Provides Stronger Mid-Range Power

The Airaid PowerAid Throttle Body Spacer, part number AIR400-591, is designed to improve off-idle and mid-range torque on select Ford F-150 and Expedition models equipped with the 5.4L engine. Its patented Helix Bore design spins the incoming air charge as it passes through the throttle body spacer, increasing air velocity and helping promote improved air/fuel mixture atomization before combustion.

This airflow enhancement is intended to deliver stronger part-throttle torque from approximately 800 rpm through 3,000 rpm, along with improved mid-range power for more responsive everyday driving. The PowerAid spacer is a true bolt-on upgrade that installs in under an hour using common hand tools. No drilling, cutting, or permanent vehicle modifications are required. Mounting hardware is included for a straightforward installation.

Key specifications and technical data:

• Brand: Airaid
• Part Number: AIR400-591
• Product Type: Throttle body spacer
• Application: Automotive performance upgrade
• Engine Compatibility: Select 5.4L applications
• Airflow Design: Patented Helix Bore
• Installation: Bolt-on installation with common hand tools
• Emissions Information: EPA compliant; CARB Executive Order D-609

What's included: Airaid PowerAid throttle body spacer and installation mounting hardware.

Fitment: Fits select 1997-2003 Ford F-150 and 1997-2004 Ford Expedition models equipped with the 5.4L engine. Verify vehicle year, engine configuration, and application details before ordering. California emissions compliance is covered under CARB Executive Order D-609.

Features:

• Helix Bore design spins incoming air to increase air velocity and support improved air/fuel atomization.
• Designed to enhance off-idle torque from approximately 800 rpm to 3,000 rpm.
• Helps provide stronger part-throttle torque and improved mid-range power.
• True bolt-on installation requires no drilling, cutting, or permanent modifications.

Fitments:
1997 Ford Expedition Eddie Bauer
1997 Ford Expedition XLT
1997 Ford F-150 Base
1997 Ford F-150 Lariat
1997 Ford F-150 XL
1997 Ford F-150 XLT
1998 Ford Expedition Eddie Bauer
1998 Ford Expedition XLT
1998 Ford F-150 Base
1998 Ford F-150 Lariat
1998 Ford F-150 XL
1998 Ford F-150 XLT
1998 Lincoln Navigator Base
1999 Ford Expedition Eddie Bauer
1999 Ford Expedition XLT
1999 Ford F-150 Base
1999 Ford F-150 Lariat
1999 Ford F-150 XL
1999 Ford F-150 XLT
1999 Lincoln Navigator Base
2000 Ford Expedition Eddie Bauer
2000 Ford Expedition XLT
2000 Ford F-150 Base
2000 Ford F-150 Harley-Davidson Edition
2000 Ford F-150 Lariat
2000 Ford F-150 XL
2000 Ford F-150 XLT
2001 Ford Expedition Eddie Bauer
2001 Ford Expedition XLT
2001 Ford F-150 Harley-Davidson Edition
2001 Ford F-150 King Ranch
2001 Ford F-150 Lariat
2001 Ford F-150 XL
2001 Ford F-150 XLT
2002 Ford Expedition Eddie Bauer
2002 Ford Expedition XLT
2002 Ford F-150 King Ranch
2002 Ford F-150 Lariat
2002 Ford F-150 XL
2002 Ford F-150 XLT
2003 Ford Expedition Eddie Bauer
2003 Ford Expedition XLT
2003 Ford F-150 King Ranch
2003 Ford F-150 Lariat
2003 Ford F-150 XL
2003 Ford F-150 XLT
2004 Ford Expedition Eddie Bauer
2004 Ford Expedition NBX
2004 Ford Expedition XLT
2004 Ford Expedition XLT Sport
2004 Ford F-150 Heritage XL
2004 Ford F-150 Heritage XLT

Air Freight Prohibited: false
Not Carb Approved: false
Carb Eo Number: D-609
Ltl Freight Required: false
Prop 65: Y
Part Type: automotive
Epa: Compliant
Carb Acknowledgement Required: false
Regular Stock: t
Units Per Sku: 1