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HLY550-401 - Holley Avenger 900 CFM EFI Throttle Body Fuel Injection System

Availability: Special Order Item
Pricing: $2,120.95


HLY550-401 Holley Avenger 900 CFM EFI Throttle Body Fuel Injection System with 75lb per hour injectors. Supports engines with 375HP to 525HP

Replace your carburetor with a “Bolt on and Go” TBI system! Avenger™ EFI throttle body kits are a direct replacement for a carburetor. Plug and play connectors make installation a snap and the Avenger's Self–tuning capabilities will have you up and running in no time. Come with all necessary parts for a complete installation. All set up is done on the included hand–held tuner so no laptop is required!

Installation Notes:

Fits all standard square flange intake manifolds. All Avenger EFI systems come with all installation components including wiring harness, sensors and in-line pump. Return fuel line to tank is not included.


• Self-tuning fueling strategy tunes while you drive - Designed for the user that wants ease of use without having to be a “tuning expert”
• Requires no laptop computer to set up or tune - Included full color OLED hand-held tuner offers simple setup and easy tuning of basic parameters such as engine idle speed. Still allows for users to change other parameters to further fine tune base calibrations: Come complete with all hardware to retrofit EFI on a non-EFI vehicle including fuel pump
• Dedicated fuel and oil pressure inputs
• Allows for computer controlled ignition timing if desired
• System can be upgraded in the future to a Holley “HP EFI System” if desired

Click On Documents Tab for Installation Instructions


  • 550-401
  • 550-401
  • 090127666845
  • Holley Performance
  • Special Order Item
  • New

Shipping Information

  • Item Requires Shipping
  • 14.0 lbs.
  • W11.8800” x H8.5000” x L17.3100”

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