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Air and Fuel› Fuel Injection Systems and Components - Electronic

Holley

TERMX STEALTH 4150, 4 INJ, LS 24X, BLACK

$2,587.95 $2,347.15 Save $240.80

SKU: H00E 550-1021

In Stock
In Stock
Ships by Jun 8
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Holley 550-1021 is a self-tuning electronic fuel injection (EFI) system designed to replace traditional carburetors. It features a "stealth" design that maintains a classic carbureted appearance while providing the benefits of modern EFI, such as improved fuel economy, throttle response, and drivability. This specific kit is compatible with GM LS engines utilizing a 24x crank sensor and a 4150-style flange intake manifold.

Fitment

Fitment Guaranteed

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on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandHolley
Part NumberH00E 550-1021
Weight20.6 lb

Videos

Ditch the Carb and Go EFI with Holley Terminator X Stealth 4500 and 4150

Ditch the Carb and Go EFI with Holley Terminator X Stealth 4500 and 4150
Holley EFI Sniper Stealth 4150

Holley EFI Sniper Stealth 4150
Holley EFI Stealth - Disguised as a Carb!

Holley EFI Stealth - Disguised as a Carb!
Holley Terminator Stealth EFI Installed - 1968 Chevelle SS

Holley Terminator Stealth EFI Installed - 1968 Chevelle SS
Holley EFI Terminator X Stealth 4150 Unboxing!

Holley EFI Terminator X Stealth 4150 Unboxing!
Don't Buy A Holley Terminator X Before Watching This Video

Don't Buy A Holley Terminator X Before Watching This Video
Terminator X Full Install and Overview

Terminator X Full Install and Overview
Why you Dont want Terminator EFI

Why you Dont want Terminator EFI
Holley Terminator X Just Got a Major Upgrade

Holley Terminator X Just Got a Major Upgrade
I am Amazed! Install & Test Holley Terminator X Stealth on my Chevy K10

I am Amazed! Install & Test Holley Terminator X Stealth on my Chevy K10

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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