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Holley Sniper 550-851 EFI 2300 2-Barrel Self-Tuning Base Kit
Holley Sniper 550-851 EFI 2300 2-Barrel Self-Tuning Base Kit

Holley Sniper 550-851 EFI 2300 2-Barrel Self-Tuning Base Kit

Universal Fit, 580 CFM CFM, 3 Emission Code, Anodized, Throttle Body Injection Style, Gold

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Holley Sniper 550-851 EFI 2300 2-Barrel Self-Tuning Base Kit
Holley Sniper 550-851 EFI 2300 2-Barrel Self-Tuning Base Kit
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We estimate this item will ship on or before May 21st.
Part # 425550851
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Important Messages:

  • This item ships directly from the manufacturer. It may take an additional 2 business days for Holley Sniper to ship this item.
  • Get FREE shipping when your order includes this item and exceeds $99! Ground shipping only in the contiguous US.
  • This item ships via Ground Shipping only. Expedited and Air shipping options are not available.


MFG. Part #:
Sold in Quantity:
580 CFM
Emission Code:
Throttle Bore:
Distributor Included:
Injection Style:
Throttle Body
Injector Size:
100 lb/hr at 58.5 PSI
Injectors Included:
Self Tuning:
Wiring Harness Included:
Throttle Body Barrels:


Put an end to mysterious air/fuel ratios, jet changes, and cold-start rough idle troubles with Holley Sniper EFI. Affordable aftermarket fuel injection is here and it couldn't be any easier to install on your vehicle. Holley Sniper EFI is a perfect match for any muscle car, classic truck, street rod, or nearly any other carbureted vehicle. Economically priced to save your hard earned money for other parts of your build; Holley Sniper EFI is a self-tuning, plug and play fuel injection system that takes all the trouble and guesswork out of your switch to modern electronic fuel injection. With over 100 years of building quality fuel systems, you can trust Holley Sniper with all your electronic fuel injection needs!

Holley Sniper EFI is packed with all the features that your car or truck needs. This throttle body fuel injection replaces any square bore or spread bore style 2-barrel carburetor. The built in ECU keeps the wiring neat and tidy with no need to run the computer and associated wiring back into the cab of the vehicle. Connect the 4 necessary wires and you're good to go. The self-learning ECU takes care of setting the baseline tune while the full touchscreen display allows you to fine tune as you please. Sniper EFI throttle bodies utilize OEM style TPS and IAC modules for dependable and serviceable use. Life is too short to hassle  with cold start issues, hesitations, flooding, and carburetor inconsistencies. Leave that old 2-barrel to rest and bring in a new era of performance, reliability, and fun with a Holley Sniper EFI system!

Easily adapts to a square flange or Q-jet flange 4 barrel intake with a Mr. Gasket adapter P/N 550-1933 (4150 Square Flange) or 550-1929MRG (Spread Bore). 

  • Direct 2300 carburetor replacement
  • Fits single and dual plane intake manifolds
  • Naturally aspirated applications only
  • Throttle body mounted ECU - no extra computers to mount or relocate
  • Capable of supporting up to 350 HP with 2 100 lb/hr injectors
  • Simple, 4 wire connection (Battery +, Battery -, Switched ignition & RPM)
  • Built in pre-set fuel pressure regulator
  • Integrated ignition timing control & coil driver
  • Color touchscreen for easy setup and gauge displays
  • Self tuning ECU means you dont have to be a computer/tuning expert to enjoy EFI
  • Gold finish
  • Sold individually

Instructions (PDF)

Application Guide (PDF)

Quick Start Manual (PDF)



  • For a naturally aspirated engine application only.
  • Not to be used for turbocharger or supercharger applications.
Some parts are not legal for use in California or other states with similar laws/regulations

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