SKU: 56135328181

Holley 550-870 Sniper Stealth 4150 Self-Tuning Fuel Injection System 4150 Flange

Sale price$719.98 Regular price$799.98
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Description

Holley 550-870 Sniper Stealth 4150 Self-Tuning Fuel Injection System 4150 FlangeOverview: The Sniper Stealth 4150 EFI system from Holley features 4, 100LB HR Fuel Injectors capable of supporting up to 650 HP naturally aspirated or 600 HP on forced induction applications. The Sniper Stealth 4150 ECU is capable of fuel map self learning and ignition timing control, improving idle stability, drivability, and wide open throttle horsepower! Did we mention that the Stealth 4150 also includes transmission kick down provisions for GM

Overview:

The Sniper Stealth 4150 EFI system from Holley features 4, 100LB/HR Fuel Injectors capable of supporting up to 650 HP naturally aspirated or 600 HP on forced induction applications. The Sniper Stealth 4150 ECU is capable of fuel map self-learning and ignition timing control, improving idle stability, drivability, and wide-open throttle horsepower! Did we mention that the Stealth 4150 also includes transmission kick down provisions for GM TH350/400, 200R4/700R4 and Ford C4/C6 applications. For a complete installation, Master Kit part # 550-870K includes a complete fuel system with an external fuel pressure regulator preset to 58.5psi, 20ft of 3/8" Vapor Guard Fuel Hose, Fuel Pump, Filters, necessary hardware, and bulkhead fitting to return fuel into the tank!

Features:

  • Bolt on 4150 Flange Carburetor Replacement
  • Throttle body mounted ECU - no extra boxes to mount
  • Supports up to 650hp with Four 100 Lb/Hr Injectors!
  • 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.
  • Only 4 Wiring Connections Required! (Battery +, Battery - , Switched Ignition & RPM)
  • An external fuel pressure regulator is required, set to a base pressure of 58.5 PSI, e.g. 12-886.
  • Integrated ignition timing control
  • High Resolution Full Color Touchscreen for Initial Setup, Tuning, and Gauge Displays
  • 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!
  • The included Genuine Bosch LSU 4.9 Wideband Oxygen Sensor provides real-time Fuel Map Learn!
  • OEM Style TPS/IAC 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
  • Available in 3 finishes: Shiny, Black and coming soon, Gold

 

Application:

Year Make Model Submodel Engine Size
Universal

 

Specs:

Brand Holley Sniper EFI
CFM 870
Emission Code 3
Finish Shiny
Flange Style 4150
Fuel Pressure 58.5 PSI
Height 3.28"
Injector Size 100 lb/hr @ 58.5 PSI
Inlet / Outlet Size 3/4-16 Female O-Ring (AN 8)
MAP Sensor 2Bar
Max Horsepower Rating 650 Naturally Aspirated
Model 4150 EFI Conversion Throttle Body
Product Type Sniper Stealth EFI
Transmission 700R4/200R4
Transmission Ford C4/C6
Transmission TH350
Warning California Proposition 65
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 56135328181

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Saltywench
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I recently tried a twin mattress topper made from bamboo-derived viscose, and I'm quite impressed. The topper is thick, waterproof, and offers excellent comfort, especially for those who struggle with back pain or sleep hot. The bamboo and polyester blend gives it a soft, cooling surface that's perfect for a restful night's sleep without the sweaty feeling often associated with memory foam. What I really appreciate is its dual function. It's breathable, allowing for good air flow, and fully waterproof, which helps keep the mattress underneath safe from spills. This is especially useful if you have kids or pets. The topper's thickness is just right—it provides great support without feeling too soft or too firm. It cradles pressure points well, offering relief to my hips, back, and shoulders. The fluffy filling holds up well over time, maintaining its softness and support. It fits securely on mattresses, thanks to a deep pocket skirt that prevents any sliding or bunching. This topper has definitely provided me with better, more comfortable sleep.
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Bunny
Whiting, US
★★★★★ 5
Soft and comfy
Color: Green, Size: Twin, Color: Green, Size: Twin
This mattress pad is much thicker and fluffier than the one I had before. With I took it out of the package, it was vacuum sealed with a note saying to leave it out in the sun for 48-72 hours or fluff it up with a hair dryer. I put it in the dryer on medium heat, which worked nicely. The pockets are really deep on this mattress pad and it fits snug. You don’t really see the shape with a sheet on top. It feels comfortable laying on top of it. It doesn’t flatten much when I’m laying down, but I imagine over time it will lose fluffiness. Overall it’s comfortable and breathable.
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Reviewed in the United States on May 31, 2026
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Draper, US
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Color: Dark Grey, Size: Queen
If your mattress is already soft, it will help. It's less than 1in thick after tumbling for 40 minutes. It did fit my queen bed and felt somewhat soft when laying down but it didn't help much as far as comfort. Quality wise it looks good, not cheap and while my sleep quality wasn't improved, it might help someone with a better mattress than mine.
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F&S
Cuba, US
★★★★★ 5
Must have for mattress comfort and protection
Color: Green, Size: Twin, Color: Green, Size: Twin
I ordered the BDEUS Twin mattress topper for a temporary mattress. The topper definitely improves comfort and regulates temperature much better than just the mattress and sheets. The cover fits deep mattress easily fitting over my 13” mattress and could easily fit a much deeper bed. The padding is thick enough to provide some additional support. This model also has a thin sheet of waterproof material to help protect your mattress against spills or liquid damage. This layer is cover by the pillow top and does not seem to make much if any noticeable noise. Overall this is a high quality cover and mattress protector in one. At <$45 at the time of this review it provides an incredible value.
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max haney
Omaha, US
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Topper
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I recently purchased the BDEUS Twin Mattress Topper Viscose Derived from Bamboo, and I am thoroughly impressed with my experience. The comfort level is absolutely a 5 out of 5. The viscose bamboo material feels soft and plush, making my bed significantly more comfortable to sleep on. I wake up feeling well-rested and supported, which has been a noticeable improvement from before. Here are some of the main pros and cons: Pros: Incredible comfort and softness, high-quality materials, fits the twin mattress perfectly, and helps with temperature regulation throughout the night. Cons: Name Overall, I give the BDEUS Twin Mattress Topper a solid 5 out of 5 stars. It has completely transformed my sleeping experience, and I would highly recommend it to anyone looking to enhance the comfort of their bed.
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