Do you have an interest in switching to EFI, yet you do not want to significantly change the look of your engine bay or run a different air cleaner? To meet the needs of many enthusiasts, Holley’s Sniper EFI division introduces the new Sniper Stealth 4150, which is modeled after Holley’s successful Ultra XP carburetor. The 4150 EFI system includes four, 100 lb/hr fuel injectors that will supports up to 650 normally aspirated horsepower or 600 forced induction horsepower.

The Sniper Stealth 4150 has a self-learning electronic control unit (ECU) mounted on the throttle body. The ECU is self-learning in conjunction with a Bosch LSU 4.9 Wideband Oxygen Sensor, so it can provide a precise fuel map for all engine demands from idle to wide-open throttle. The 4150 EFI provides quality idle stability, outstanding drivability, and is capable of ignition timing control if desired.

The Sniper Stealth 4150 is a bolt-on to any 4150-manifold flange. The ECU is mounted inside the throttle body. There are four injectors that support up to 650 normally aspirated horsepower. A high-pressure fuel crossover line is included, and all the wiring exits below the rear injector cover

If electronic ignition timing is not selected, a timed spark port is located on the throttle body, for the vacuum advance on the distributor. The master kit includes an external fuel pressure regulator set to 58.5 psig, a fuel pump, the fuel filters, 3/8-inch Vapor Guard fuel hose, a bulkhead fitting for the return line at the tank, and all the mounting hardware for a trouble-free installation.

The Sniper Stealth 4150 is constructed with an OEM-type throttle position sensor (TPS), idle air control valve (IAC), and manifold absolute pressure sensor (MAP), which will provide years of reliable service. To setup, tune, and view gauge displays, the 4150 includes a handheld EFI monitor with a high-resolution full-color touchscreen, so there is no need for a laptop.

To connect the oxygen sensor to the exhaust, a 2.25-inch clamp-on sensor kit is included. The Sniper Stealth 4150 is available in a shiny or black finish, and it will soon be available in gold. If you have an interest in upgrading to EFI, check out Sniper EFI for more information.

Above left:  The high-resolution full-color touch screen provides easy initial setup. To answer each screen prompt, simply depress the touchscreen in the calibration wizard. From that point, the ECU begins self-learning to provide optimum drivability. There is no need for a laptop. Above right: The 4150 EFI has a timed vacuum port for a vacuum advance unit on a distributor. If the factory kickdown linkage is still being employed, a Chrysler kickdown lever (sold separately by Holley) will have to be added to the throttle lever for proper operation.