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Ships within 48 hours · Estimated delivery Jul 11 - Jul 16
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Description
Holley 550-870K Sniper Stealth 4150 Self-Tuning Fuel Injection System Master KitOverview: 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. Part # 34-42 is required for a bolt-in installation.
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)
- External fuel pressure regulator required, set to a base pressure of 58.5 PSI, such as 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 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
- 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:
- 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
4.5 ★★★★★
Based on 186 reviews
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Product Reviews
★★★★★ 5
Great buy
Size: 11, Color: Tan
Great fit comfortable look good
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 12, 2026
★★★★★ 5
Great shoes
Size: 14 Wide, Color: Black
My shoes look good and feel good and now I’m going to purchase the brown pair I saw
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 24, 2026
★★★★★ 4
Don’t buy for restaurant industry
Size: 10.5, Color: Black, Size: 10.5, Color: Black
Good looking shoes, fairly comfortable and good value based on the description shared, so I don’t feel it’s fair to rate them lower than 4 stars. I had high hopes for them based on previous reviews from others saying they wore them in the food and beverage industry that mentioned their quality and durability, however I strongly recommend looking elsewhere if you do. I purchased these to wear working in a full service upscale restaurant and in less than two months have managed to have torn the material on the middle exterior section and the bottoms of the shoes are already completely worn down. Good design, but the durability needs to be improved if they’re to hold up for that industry.
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Reviewed in the United States on July 18, 2025
★★★★★ 1
DO NOT BUY (lasted less than 7 months)
Size: 11, Color: Black, Size: 11, Color: Black
I bought these for work as a bartender in August of 2025. By December, the tops were scuffed, frayed, and peeling beyond repair, and by February, the soles were coming off. I’ve never had a pair of shoes with such low quality.
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Reviewed in the United States on April 11, 2026
★★★★★ 5
Most comfortable shoes, right out of the box!
Size: 8.5, Color: Cognac Napa Leather
Oh my! So, my ordering of shoes online has been hit or miss - 1/2 size too big or too small; too wide or not wide enough. Enter these Marc Joseph shoes… such a game changer. They fit like a glove, exceptionally comfortable, and easy to slip in and out of. I like them so much that I am shopping for another pair. So far, the size, quality, fit, feel, look, and comfort make this pair my dedicated first pick. Btw, I have been wearing them for six hours and they are still very comfortable! I highly recommend these shoes.
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Reviewed in the United States on September 28, 2025