The Holley Sniper 2 EFI Returnless Drop-In Module kit brings self-tuning fuel injection to common four-barrel, 4150-flange carbureted engines. This black-finish kit pairs the Sniper 2 throttle body with a 3.5 in. handheld display, the Power Distribution Module (PDM), and a universal returnless drop-in fuel module.
Key Features:
- Includes the Power Distribution Module (PDM), which isolates core EFI and ignition wiring into a single positive-lock connector block for simplified installation
- Redesigned throttle shaft and plate geometry for a smoother, more linear throttle feel
- Next-generation ECU with improved RF noise and interference resistance for reliable operation on older vehicle wiring
- Includes a genuine Bosch LSU 4.9 wideband oxygen sensor for real-time fuel map learning
- Onboard contactless magnetic TPS sensor for accurate, drift-free throttle position readings
- Cast-in fuel crossover from the primary to secondary fuel rail
- "Hidden Harness" wiring exits from the rear of the throttle body for a clean installation
- Only four wiring connections required: Battery+, Battery-, Switched Ignition, and RPM
- Built-in calibration wizard builds a base fuel map from a few simple engine questions - no laptop required
- Compatible with the full Sniper EFI Ecosystem, including HyperSpark ignition, fuel systems, and multiple display options
- Each throttle body is individually serialized for streamlined customer service and warranty support
Specifications:
- Finish: Black
- User Interface: 3.5 in. Handheld
- Fuel System: Universal returnless drop-in module
- Power Distribution Module: Yes
- Part Number: 550-511-3PD
This is a returnless-style, tank-mounted drop-in fuel module variant of the Sniper 2 EFI platform; a full specification table was not available in the source data for this listing (see note below), so specs are limited to confirmed details plus the standard Sniper 2 4150-flange platform figures shared across this product family (800 CFM, 100 lb/hr injectors, 58.5 PSI operating pressure, up to 650 hp NA / 575 hp boosted).
Nitrous control is not supported in Sniper 2 EFI software.
FAQ
What engine and carburetor flange does this kit fit?
Like the rest of the Sniper 2 EFI family, it's built for common four-barrel, 4150-flange carbureted engines.
What fuel delivery style does this kit use?
It uses a universal returnless drop-in fuel module, mounted inside the tank.
Does this kit include the Power Distribution Module?
Yes, the PDM is included, simplifying wiring by isolating the core EFI and ignition connections into one location.
Do I need a laptop to tune it?
No. The 3.5 in. handheld's calibration wizard asks a few simple questions and builds a base fuel map automatically.
Is nitrous control supported?
No, nitrous control is not supported in Sniper 2 EFI software.