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Holley Sniper EFI

Holley Sniper Stealth 4150 Master Kit - Shiny

Supports Up To 650HP - 3.5 in. Handheld Monitor - Carburetor Styling - Return Fuel System

Part # 550-870K
1 Review

Holley Sniper Stealth 4150 Master Kit - Shiny

Estimated Ship Date: 05/17/2024
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Emissions

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

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Holley's Sniper Stealth 4150 Master Kit gives you carburetor styling but functions just like the Sniper! A 4150 stealth is a great way to upgrade your ride to fuel injection in a cost-efficient way with just 4 simple connections required. Take your build to the next level and take advantage of improved engine performance, better MPG's and easier starting. This kit supports up to 650hp naturally aspirated and 600hp boosted with Four 100 Lb/Hr injectors! You don't have to be a computer wiz or tuning professional to run a sniper kit on your build. Simplicity is what we strive for! Our calibration wizard allows you to just answer a few questions about your engine and the system will begin self-tuning with no laptop required. Use the high resolution 3.5" full color touchscreen for tuning and gauge displays. The stealth 4150 also includes transmission kick down provisions for GM TH350/400, 200R4/700R4 and Ford C4/C6 applications. The 4150 includes a complete fuel system consisting of all necessary hardware to return fuel into your tank. Additionally, you're getting a 4.9 wideband oxygen sensor with a leak free oxygen sensor, oem style TPS/IAC, fuel pressure regulator, all Stainless Steel T-Bolt clamps and a Stainless Steel weldable flange. Once you made your conversion to EFI, don't stop there! Sniper is an Ecosystem! This kit pair's seamlessly together with Holley's Sniper Hyperspark Ignition, Fuel System's, Air Cleaners, Throttle Body & Digital Dash to unlock the full potential of your build. Part # 34-42 is required for a bolt-in installation.

Features:

  • Bolt on 4150 Flange Carburetor Replacement
  • Simple Calibration Wizard (answer a few questions about your engine and it creates the base map, then starts tuning on its own!) - NO laptop required!
  • Self-tuning ECU means you don’t have to be a computer/tuning wiz to have EFI!
  • Only 4 Wiring Connections Required! (Battery +, Battery - , Switched Ignition & RPM)
  • Supports up to 650hp with Four 100 Lb/Hr Injectors!
  • Throttle body mounted ECU – no extra boxes to mount
  • High Resolution Full Color Touchscreen for Initial Setup, Tuning, and Gauge Displays
  • All of the wiring exits below the rear fuel injector cover, for a completely stealth installation.
  • Timed spark part for vacuum advanced distributors located under the front fuel bowl, for easy access to the distributor.
  • Air entry is machined to fit most stock style air cleaners with air cleaner locator provisions.
  • External fuel pressure regulator required, set to a base pressure of 58.5 PSI, such as 12-886.
  • Integrated ignition timing control
  • The included Genuine Bosch LSU 4.9 Wideband Oxygen Sensor provides real-time Fuel Map Learn!
  • OEM Style TPS/IAC and Fuel Pressure regulator, for years of dependable service.
  • Included clamp-on oxygen sensor kit for 2.25" exhaust ensures a leak free oxygen sensor installation, with Stainless Steel T-Bolt clamps and a Stainless Steel (Weldable) oxygen sensor flange
Brand Holley Sniper EFI
CFM870
Emission Code3
FinishShiny
Flange Style4150
Fuel Pressure58.5 PSI
Height3.28"
Injector Size100 lb/hr @ 58.5 PSI
Inlet / Outlet Size3/4-16 Female O-Ring (AN 8)
MAP Sensor2Bar
Max Horsepower Rating650 Naturally Aspirated
Model4150 EFI Conversion Throttle Body
Product TypeSniper Stealth EFI 4150 Master Kit
Sale CategoryAir and Fuel Delivery
Transmission700R4/200R4
Ford C4/C6
TH350
UPC090127078396
Part Number550-870K
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
Sniper EFI SD Card Contents
Sniper EFI SD Card Contents
Holley EFI Dealers
Do you need a custom kit built for your application? Do you need a system installed and tuned? Click here to find the Holley EFI dealer in your area!
Part # 534-247 is required to complete installation.

Have a question about this product?

  • Question

    Can this part be used with a wet nitrous system? It does not have to control the system. There would be a separate control for this.

    By Tom S. on July 30, 2021

    Answer
    Hi Tom, Thank you for contacting Holley tech. Part number 550-870K is compatible with nitrous as long as the combined HP does not exceed the 650 HP rating. If you have any further questions or need immediate assistance please contact our Tech Line at 1-866-464-6553. Thanks, Cole.
    Helpful?
  • Question

    1965 /1966 Ford Mustangs with a 289 / 302 and C-4 trans have a metal kick down rod coming from the trans that hook to special linkage on the Holley carb. Do you have provisions for this on this Injection unit? THANKS!!! chris

    By Christopher S. on November 18, 2019

    Answer
    Yes! The kick-down lever is on the side of the throttle body. It is designed to work just like the C4 kick-down linkage on a Holley carburetor.
    Helpful?
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Some parts are not legal for use in California or other states with similar regulations.