When Holley introduced its Sniper Throttle Body EFI system back in 2015, it was a game-changing moment in the history of fuel injection conversion kits. The Sniper offered a straightforward way for the home gearhead to switch from a carburetor to a modern, self-tuning EFI setup—no computer engineering degree required.

And now thanks to the popularity of the first-generation Sniper EFI kits, Holley’s taking EFI evolution another big leap forward with its Sniper 2 Self-Tuning Electronic Fuel Injection Systems.

Holley Sniper 2 EFI Throttle Body with black finish
The throttle body contains the fuel injectors and ECU, with all of the connections discretely exiting out of the back of the unit. (Image/Holley)

In a nutshell, Holley’s engineering team took what it learned from almost a decade’s worth of real-world testing since the original Sniper came out and released the all new Sniper 2, which promises to make the switch to fuel injection even more hassle-free.

What’s New in the Sniper 2 EFI System?

For starters, Holley redesigned the heart of the system: the throttle body itself.

You’ll see obvious upgrades, like how the throttle bypass hose is now cast directly into the housing to reduce the chance of leaks.

You may also notice how the throttle blades have been tweaked to promote better throttle response.

But perhaps the biggest update you can see with the naked eye is the revised throttle linkage. Holley changed the throttle linkage lever to include kickdown provisions for the GM Turbo 350, and 200R4/700R4 transmissions. Running a Ford C4 or C6? Holley’s got you covered there too with a bolt-on bracket that connects right to the linkage.

Updated throttle body bracket on holley Sniper 2 efi kit for trans kickdowns
The Sniper 2 System makes it really, really easy to attach you automatic transmission kickdown now. (Image/Holley)

But the Sniper 2’s enhancements are way more than skin deep.

Inside the throttle body is an all-new ECU module. Thanks to customer feedback, the Sniper 2’s computer “brain” is now better shielded from electrical interference from, say, a vintage ignition system or AM/FM radio.

Better still, the throttle position sensor has been refined and features a non-contact design for improved reliability and precision.

And all electrical connections exit discretely out the back of the throttle body, in what Holley is calling its “Hidden Harness” design. That simple tweak goes a long way towards maintaining a vintage aesthetic in your old-school hot rod, cruiser, or muscle car.

And if you’re counting at home, you’ve only got to make four connections to get your Sniper 2 system ready to go: battery positive, battery negative, your switched ignition source, and RPM hookup. The rest of the sensors and fuel system components connect with plug-and-play simplicity.

How to Setup & Tune the Holley Sniper 2 EFI System

One of the hallmarks of the original Holley Sniper fuel injection system was its easy setup and tunability. Indeed, the whole system was essentially self-learning, so you simply walk through the setup wizard, answer a few easy questions, and from there, the ECU will adapt as you drive to optimize your air/fuel ratio for the best performance.

And that philosophy carries through into the new Holley Sniper 2.

Setting up and tuning your Holley Sniper 2 EFI system is done via a standalone controller module or through Bluetooth on your Apple or Android smartphone. (Image/Holley)

No complex graphs or charts here, Holley’s Sniper 2 uses the familiar tuning wizard and once you’re done, the system will finish the job and adjust as you drive—making the entire setup smooth and effortless.

Though if you know what you’re doing, Holley’s system lets you tweak variables and adjust your engine tune for excellent customization too.

For the new Sniper 2 EFI system, setup happens in one of three ways (and none of them involve fiddling with a laptop).

Tuning Option 1: The Standard 3.5 Inch Display Controller

  • The first option is Holley’s compact three-and-a-half inch handheld color display that is similar to the one used on the first-gen Sniper systems. As an added bonus, once you’re done running through the setup wizard, you can keep the controller plugged in to be used as a datalogger.

Tuning Option 2: The Larger 5 Inch Display Controller

  • Next up is Holley’s larger five inch display. The bigger module retains all the features of the 3.5 inch version, yet it also includes a GPS speedometer with three different selectable gauge display screens. Better still, Holley includes a handy windshield mount, so you can use the whole thing as a supplemental gauge panel.

Tuning Option 3: Android or Apple Compatibility via Bluetooth

  • Finally, you can skip the extra displays and do the whole EFI setup and tuning thing with your Android or Apple smartphone. With an optional Bluetooth module, you just connect to the Sniper 2 using Holley’s downloadable app and you’re on your way.

The Sniper 2 EFI System Supports up to 650 hp Naturally Aspirated or 575 horsepower Under Boost.

What’s Included in the Holley Sniper 2 EFI System Kits?

The Sniper 2 system continues to be plug and play, and Holley tells us this new evolution now works even better with Holley’s other performance parts. Holley’s goal here is to create a modular EFI conversion system that’ll integrate seamlessly with Holley’s complementary products, like its Hyperspark distributors, fuel pumps, regulators, and beyond.

In fact, Holley’s got complete packages that include a fuel plumbing system, giving you a single-SKU solution for updating an older, carbureted car to modern fuel injection.

Better still, check out Holley’s new Power Distribution Module that makes it way, way easier to integrate your engine’s ignition control into the Holley Sniper 2 system. You may not need the PDM here for a simple installation, but if you’re planning on running ignition control now or later, it’ll take a ton of hassle out of the job. See how this handy module works in this quick video:

In short, Holley’s new Sniper 2 design makes an EFI conversion almost effortless, and it offers an entire ecosystem of other fuel and ignition components designed to work perfectly within the Sniper 2 system.

Which Holley Sniper 2 EFI Kit Should I Choose?

Holley bundles its Sniper 2 kits in a handful of packages, so you can get exactly what you need for your particular setup. And the throttle body itself is available in either a natural or black finish to match whatever look you’ve got going on under your hood.

Here are a few of the more popular Holley Sniper 2 EFI Conversion Kit packages. Click the links on the part numbers below to get all the info on the parts included in each package:

Holley Sniper 2 EFI Throttle Body kit with contents
Holley makes the Sniper 2 throttle body available separately, or with a handy Master Kit (seen here) that includes vital fuel system components to get your system up and running. (Image/Holley)

Video Overview of the New Holley Sniper 2 Throttle Body EFI System

More of a visual learner? Yeah, us too. Check out this video from Summit Racing. It’ll give you an up-close look at the Sniper 2 throttle body EFI setup, along with some key related components.

Check it out below:

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