Holley Sniper In-Tank Fuel Pump
What the Holley Sniper in-tank fuel pump is
The Holley Sniper in-tank fuel pump is an electric fuel pump module designed to sit inside the fuel tank rather than outside it. In-tank placement helps keep the pump cooler, reduces priming issues, and is common on EFI conversions where a reliable high-pressure supply is needed. Holley sells these pumps as part of the Sniper EFI ecosystem, including complete modules for factory-style tanks and retrofit modules for aftermarket or custom tanks.
Immediate answer
If you are deciding whether a Holley Sniper in-tank fuel pump fits your build, the short answer is that it can work well for many EFI applications, but the correct part depends on your tank design, fuel system pressure target, and whether you need a return-style or returnless arrangement. A common reference point is the Holley 19-350 Sniper 340 LPH in-tank fuel pump module, which supports high-flow EFI fuel delivery. For aftermarket or fabricated tanks, Holley 19-365 retrofit modules are often used because they bolt into a flat surface and accept a drop-in pump assembly.
Holley 19-350 Sniper 340 LPH in-tank fuel pump module
The Holley 19-350 is an in-tank fuel pump module rated at 340 liters per hour. It is intended for high-horsepower EFI systems where the pump must supply enough fuel volume at operating pressure. This module is commonly used with Sniper EFI throttle bodies and other Holley EFI systems. It includes an internal pump, level sender provisions, and a mount designed for a specific tank opening, so fitment depends on the tank's mounting flange and depth.
Holley 19-365 in-tank retrofit fuel pump modules
The Holley 19-365 retrofit modules are made for builders who need an in-tank pump but do not have a factory-style opening. These modules mount through a hole cut into the top of a metal or plastic tank and are often used in muscle cars, trucks, and custom fuel tanks. They give a sealed in-tank installation while allowing the pump and sender to be serviced without welding or using factory-specific tank hardware. As with the 19-350, the 19-365 family includes high-flow pump options, but the exact flow rating, sender resistance, and included components can differ by sub-model.
Compatibility with Holley Sniper EFI
A Holley Sniper EFI system expects steady fuel pressure at the throttle body or injector rail, often in the range used by Sniper installations. An in-tank pump reduces the chance of vapor lock and feed starvation compared with some frame-mounted or external pumps. The pump must still match the system's pressure and volume needs. A 340 LPH pump can support substantial power, but fuel line size, regulator setting, return line, and wiring also affect final performance.
Return-style and returnless setups
Many Sniper in-tank pump modules are used in return-style systems, where a regulator sends unused fuel back to the tank. Some installations use a returnless configuration with an in-tank regulator or a PWM controller. The pump module must be chosen for the intended plumbing. A module with only a feed port cannot be directly used in a return-style layout without modification, and a returnless module may not suit a system that requires an external regulator.
Tank depth and mounting flange
In-tank pump modules are sensitive to tank depth. A module that is too tall will bottom out or hold the pump above the tank floor, while one that is too short may leave fuel below the pickup. Retrofit kits are usually adjustable or available in depth ranges, but the exact tank measurement should be compared with the module's stated range. The mounting flange bolt pattern and gasket shape also need to be checked against the tank opening.
Sender and gauge compatibility
Some Holley Sniper in-tank pump modules include a fuel level sender. The sender's resistance range should match the gauge, especially in restoration or swap projects. If the sender resistance is not compatible, the gauge may read incorrectly even though the pump works. Holley offers different sender ranges on some modules, so the vehicle's existing gauge or aftermarket cluster should be considered.
Wiring and fuel pump control
A high-flow in-tank pump draws more current than a low-pressure carburetor pump. The supply wire, ground, relay, and fuse or circuit breaker should be sized accordingly. Sniper EFI systems can often control the pump through a relay output, but the pump should not be powered continuously with undersized wiring. The pump module should be installed with its bulkhead connector sealed so fuel vapor cannot escape at the tank.
Common installation cautions
In-tank pump work requires draining and venting the tank and avoiding ignition sources. Fuel-resistant submersible hose, proper clamps, and the correct gasket or O-ring are necessary. The pump should sit square on its mount, and the strainer or pre-filter should not be pinched. After installation, a short key-on test can prime the system, but the engine should not be started until fittings and the regulator are checked for leaks.
What to verify before choosing
Tank opening size and bolt pattern; Tank depth at the pump mounting location; Fuel pressure target for the Sniper EFI system; Return-style or returnless plumbing plan; Fuel level sender resistance for the gauge; Required flow rate in liters per hour or pounds per hour; Feed and return line size and fitting type
When an in-tank pump is the practical choice
An in-tank pump is especially useful for a Sniper EFI conversion because it can provide consistent suction, reduce under-vehicle pump noise, and simplify the fuel supply path. It is also a common replacement path when a factory in-tank pump is weak or when converting an older vehicle to EFI without relying on an external pump and its separate mounting and cooling concerns.
Limits of this guidance
This article does not identify a single universal part number for every Sniper application. Exact fitment requires the tank dimensions, existing sender range, target horsepower, and fuel pressure. Holley's 19-350 and 19-365 families cover many common builds, but sub-models and accessories vary. Availability and pricing should be confirmed through a parts retailer or Holley dealer for the specific vehicle and tank.