Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
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:
- 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
4.2 ★★★★★
Based on 1012 reviews
Sort
Product Reviews
★★★★★ 3
below average value but decent quality on this 95.4% Polyester, 4.6% Spandex dress shirt
Special Size: Black Buttons, Size: Large, Color: Sky Blue, Special Size: Black Buttons, Size: Large, Color: Sky Blue
At $20 when I picked this up, it was overpriced for what it was. I'm held accountable to the value assigned to me at the time I select to review it, so I review the value based on what was assigned not on what it later becomes if they discount it. As I write this I can see it is in a value range it should have been for me, but I'm still reviewing it at the $20. That's overpriced on a 95.4% Polyester, 4.6% Spandex shirt (i.e., non-cotton) and so the value here is a 1/5 or 2/5, say 1.5/5 for it. In terms of quality, this is a poly dress shirt. Still, I'd call this a 4/5 for what it is.
The standard is cotton, and in my experience, as someone in ties and collared shirts all day, I would note that I do prefer a 95 cotton/5 spandex blend, with the challenge that its not the most wrinkle free material. This blend, 95 poly/5 spandex, is a very wrinkle free and smooth feeling material. Poly has better durability than cotton despite feeling thinner, because it won't fray as much. That said, even though it's lightweight, poly will make you hotter because it doesn't breathe like cotton. It feels light, so you think it is going to be cooler, but in practice actually isn't really if it's a hot day. It can make you sweat more.
That said, many people like poly blends for the ease of maintenance. I've given up dry cleaning, just too much, and I do like to avoid an iron, so I tested this out because of it. For me this fit well. I ordered a large (typically I prefer to wear a 16.5/34/35, and I'm 5'11, 185) and this fit well. It's not a slim fit (tapered bottom) for those who might complain about extra material. But it fit well. I put it through both the wash and dryer. It did not shrink (poly usually doesn't) to be out of size, but was fine, and of course came out without wrinkles. The collars have no stays, these poly shirts hardly ever do, but I have found they mostly remain flat, since the material doesn't tend to wrinkle, and thus my points stay in place just fine.
At a 1.5 on value and a 4 on quality, this is a 2.75/5 average for me. Again, value plays a big part for me. So, full disclosure a better value would have raised my rating on this. But hopefully, based on what I covered above, you have enough to figure out if this shirt is worth it to you or not.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 2, 2026
★★★★★ 5
Thev quality and size
Special Size: Black Buttons, Size: Large, Color: Grey
It's good fit
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 21, 2026
★★★★★ 5
Nice dress shirt
Special Size: Black Buttons, Size: Large, Color: Grey
This shirt is a super soft and an awesome style, which I really love. The material is a soft cotton and that doesn’t irritate my skin. It is breathable, but also keeps you relatively warm. It’s very nice looking on and would be okay for everyday wear. It has been used many times going out with jeans or shorts out. I wash and dry it regularly in a machine and still looks just as new as the out of box condition. There is no pilling, fabric change, or shrinking. The style is flattering, cut well, and runs true to size. Other shirts owned feel similar to this one, which meets expectations and is a nice shirt for the price. I do wish it had a pocket though. Ultimately would purchase again.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 7, 2026
★★★★★ 5
Sharp-looking business shirt at a great price
Special Size: Black Buttons, Size: X-Large, Color: Rhine Blue
This long sleeve dark blue shirt is a great choice for a business casual look. The "Rhine Blue" color really stands out — it’s very bold without being over the top, and it gives the shirt a sharp, polished appearance.
The stitching is very well done, with clean lines and no loose threads, which adds to the overall quality. It fits nicely and maintains a crisp look throughout the day.
The material is mostly polyester with some spandex, so it feels smooth, lightweight, and is actually breathable. It stays comfortable during long wear and doesn’t feel heavy or restrictive.
Overall, it’s a sharp, well-made shirt that delivers both style and comfort at a great level. It was a good deal at the original price of about $20, but at the new price of about $15, it's an excellent deal. I may get another in a different color.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 29, 2026
★★★★★ 5
Very comfortable and looks great!
Size: X-Large, Color: Navy Blue, Size: X-Large, Color: Navy Blue
This shirt is surprisingly really nice for the price. Really nice even regardless of the price. It fits and looks great on my hubby. We liked it so much that I bought him another one in a different color. Will probably even buy more. The large ran a little small, so we got him an extra large and it was great.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 6, 2026