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Holley Sniper EFI

Holley Sniper EFI Stealth 4500 - Black

Part # 550-842
1 Review

Supports Up To 1500 HP - 3.5 in. LCD Touchscreen - 8 x 100 lb./hr. Injectors

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Holley Sniper EFI Stealth 4500 - Black

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$2,149.95
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Emissions

This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles.

See Emissions Details
Featuring (8) 100 lb./hr. fuel injectors, the Stealth 4500 is a great option for any build looking to make between 800-1500 HP naturally aspirated or 1250 HP forced induction engines. This is a great pairing for dragster, pro street, and other aggressive applications with multiple input and output options for sensors, switches, and relays. Flowing 1440 CFM for larger cubic inch engines, the Dominator style main body four bolt air cleaner flange keeps increased amount of air moving. Included is a built in MAP sensor rated at 2.5 BAR and programmable launch control via 2-step along with a timing retard option, which can be triggered by the trans-brake input. Make your classic drive like a modern fuel injected vehicle, including better cold starts, smooth drivability, and improved fuel economy. Sniper Stealth 4500 was designed to be installed at home in your garage with a few tools and the support of Holley's comprehensive installation manuals and online videos. The high resolution 3.5โ€ LCD touchscreen user-friendly setup wizard has you answer a few simple questions about your engine and the system will begin self-tuning with no laptop or tuning experience required. If you're looking for a high-performance fuel injection system that delivers power, efficiency, and ease of use, look no further than the 4500 EFI system. Take full control and make the conversion to EFI with ease with many additional accessories such as HyperSpark, air cleaners, digital dashes, and more.

Features:

  • Supports up to 1500 HP naturally aspirated or 1250 HP forced induction
  • 1440 CFM for large cubic inch engines with 2.125” throttle plates
  • Dominator style 4 bolt air cleaner flange
  • Compatible with blow through or draw through forced induction applications
  • (4) wiring connections required for throttle body installation (Battery+, battery-, switched ignition, and RPM)
  • Built in 2.5 MAP sensor for improved performance
  • OEM designed Throttle Position Sensor and Idle Air Control module for dependable reliability
  • -8AN fuel inlets for greater fuel delivery
  • Bosch LSU 4.9 Wideband O2 Sensor provides real time fuel map learning, with a no welding stainless steel O2 flange and T-bolt clamps
  • ECU mounted to throttle body removing extra mounting
  • Self-tuning ECU with intuitive setup calibration wizard creating a base tune
  • (6) programmable ground outputs and (5) programmable ground inputs used to control external relays, switches, and other devices
  • (3) programmable 0-5V sensor inputs for oil and fuel pressures or monitor nitrous and other critical information
  • Customizable secondary output for fuel pump activated by throttle position, RPM, or boost signal
  • Programmable boost control available, software includes Boost vs. RPM, Boost vs. Time Curve, set Target Launch Boost Control Pressure, and Target Air/Fuel Rations in relation to boost control levels
  • Single stage pulse width modulated progressive or nonprogressive nitrous controller that’s capable of controlling nitrous and fuel solenoids for wet or dry nitrous setup
  • Integrated timing control for assisting with heavy boost, load conditions, or idle
  • Programmable launch control via two-step along with a timing retard option, triggered with trans brake input
  • 3.5” LCD touchscreen handheld for real time data logging, initial setup, tuning, and gauge displays to view and monitor parameters with SD card to save key information
United States Coast Guard Approved
Certified to ISO 8846, SAE J1171 Requirements
Accelerometer SupportNo
Air Metering StyleSpeed Density
Boost ControlYes
Brand Holley Sniper EFI
CAN-BUS SupportNo
CategoryAir and Fuel Delivery
CFM1440
Coast Guard ApprovedYes
Coil Per Cylinder Ignition SupportNo
Datalogging SupportYes
Distributor IncludedNo
Distributor Included?No
Dry Nitrous ControlYes
e85 SupportNo
EGT SupportNo
Emission Code3
FinishBlack
Flange Size4500
Flange Style4500
Forced Induction SupportYes
Fuel Filter IncludedNo
Fuel Hose IncludedNo
Fuel Injectors IncludedYes
Fuel Pressure58.5 PSI
Fuel Pressure RegulatorNo
Fuel Pressure Regulator IncludedNo
Fuel Pump IncludedNo
Grade TypePerformance
Height3.85"
Idle Air Control Motor IncludedNo
Ignition Timing ControlYes
Individual Cylinder Fuel CorrectionsNo
Injector Quantity8
Injector Size100 lb/hr @ 58.5 PSI
Inlet / Outlet Size8AN
Intake Manifold IncludedNo
Knock Retard SupportNo
MAP Sensor2.5Bar
Max Horsepower Rating1250 Forced Induction, 1500 Naturally Aspirated
Maximum Injector Quantity Supported8
Multi-Stage Nitrous ControlYes
Part TypeFuel Injection Conversion Kit
Product TypeSniper EFI 4500
Progressive Nitrous ControlYes
Self-TuningYes
Sub CategoryService Kits
Throttle Bore2.125 inch
Throttle Position Sensor IncludedYes
Traction Control SupportNo
User Interface3.5 in Handheld
User-TuneableYes
Wet Nitrous ControlYes
UPC090127045275
Part Number550-842
3

This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles.


The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles:

  • 1965 and older U.S. manufactured California Certified vehicles
  • 1967 and older U.S. manufactured Federally Certified vehicles
  • 1967 and older Foreign manufactured vehicle


WARNING: It is against the law to install this part on an Emissions Controlled Vehicle


The following vehicles are considered Emissions Controlled Vehicles:

  • 1966 and newer U.S. manufactured California Certified vehicles
  • 1968 and newer U.S. manufactured Federally Certified vehicles
  • 1968 and newer Foreign manufactured vehicle
Not to be used on engines producing 800 HP or less. Racing fuels may shorten the service life of the O2 wideband sensor. Required Holley P/N 12-848 for external fuel pressure regulator or Holley P/N 12-848KIT that includes a gauge. For marine installations, a flame arrestor is legally required. We recommend Holley P/N 720-1 or 720-11 Flame Arrestor, along with Holley P/N 720-31 or 720-33 Flame Arrestor Vent Tube to ensure proper function, safety, and compliance.

Have a question about this product?

  • Question

    What fuel pump and regulator do you recommend for an 900HP 540 BBC bracket dragster? (Nothing trick) It does have Mikes Fab Shop S.S. headers with an O2 port in each header. and can I use my 7AL3 box? 4500 stall converter, 1900 LBS with me and ran 7.90''s with a conventional 4500 setup and belt pump on gas. (It is a Enderle 7 GPM fuel pump) Will this pup work? or should I sell it with the carb? Thanks Bob Lupini

    By Bob L. on July 13, 2019

    Answer
    Fuel system recommendations are in the instructions. https://documents.holley.com/199r11322r.pdf That being said, the 12-1500 is the fuel pump that we would recommend for your application.
    Helpful?
  • Question

    Does the sniper EFI 4500 fuel injection system come with everything to install in to a vehicle or do I have to bye everything separately?

    By Tait L. on July 26, 2021

    Answer
    Thank you for contacting Holley Tech Service. You will need to get the Fuel system components separate. There is not going to be a master kit that will allow you everything you need to go with the EFI system. This will come with all of the harnesses and the throttle body, Hand Held and O2 sensor components. The fuel pump, pre and post-filters, and a regulator along with hose and fittings will need to be purchased separately. Thanks, Matthew
    Helpful?
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Some parts are not legal for use in California or other states with similar regulations.