When it’s time for enthusiasts to upgrade their car to electronic fuel injection (EFI), One name is considered the go-to source — Holley Performance. For years, the fuel delivery company has been offering a multitude of EFI-delivery options, and the company has just released two more: The Stealth Sniper, and the Modular Lo-Ram.
If you have always had an interest in adding EFI to your classic but didn’t care for the ‘90s-appearing throttle body, this next product should quell your concerns. The Sniper Stealth 4150 EFI system from Holley features four, 100lb/hr fuel injectors capable of supporting up to 650hp on naturally aspirated applications, or 600hp on forced-induction applications.
The Sniper Stealth 4150 ECU is capable of fuel map self-learning and ignition timing control, improving idle stability, drivability, and wide-open throttle horsepower. Let’s not forget, the Stealth 4150 also includes transmission kick-down provisions for Turbo 350/400, 200R4/700R4, and Ford C4/C6 applications.
The master kits include a complete fuel system with an external fuel pressure regulator that is preset to 58.5psi, 20-feet of 3/8-inch Vapor Guard fuel hose, fuel pump, fuel filters, necessary hardware, and bulkhead fittings to return fuel into the tank.
Features:
- Bolt-on 4150-flange carburetor replacement
- Throttle body-mounted ECU — no extra boxes to mount
- Supports up to 650hp with four 100 lb/hr Injectors
- Includes high-pressure fuel-crossover line
- All of the wiring exits below the rear fuel injector cover for stealth installation.
- Timed-spark port for vacuum-advanced distributors
- Air entry is machined to fit most stock-style air cleaners with air cleaner locator provisions.
- Only four wiring connections required (Battery Positive and Negative, switched ignition and RPM)
- External fuel-pressure regulator set to a base pressure of 58.5 PSI, such as 12-886.
- Integrated ignition timing control
- High-resolution color touchscreen for initial setup, tuning, and gauge displays. The simple calibration wizard asks a few questions about your engine and it creates the base map, then starts tuning on its own — no laptop required.
- Self-tuning ECU means you don’t have to be a computer/tuning wiz to have EFI
- The included Bosch LSU 4.9 Wideband Oxygen Sensor provides real-time fuel map learn
- OEM-style TPS/IAC and fuel pressure regulator
- Included clamp-on oxygen sensor kit for 2 1/4-inch exhaust ensures a leak-free oxygen sensor installation, with stainless steel T-Bolt clamps, and stainless steel (Weldable) oxygen sensor flange
- Available in three finishes: shiny, black, and coming soon, gold
If a modern look is more your style, then the new Lo-Ram Modular Intake Manifolds might be the perfect option. These modular Lo-Ram intake manifolds are designed for LS engines with cathedral ports and can be configured for turbocharged and centrifugally supercharged applications.
The intakes have a peak power limit of 7,000 to 8000rpm, and this ultra-low design is perfect for any high-revving LS engine stuffed into a small engine compartment. The Lo-Ram intake manifolds will work with OE or aftermarket cylinder heads, and a 105mm throttle body such as Holley’s part number 112-581. The fuel-rail kits come with two sets of brackets: a set for long (usually standard length) fuel injectors and a set for short (such as Pico, or LS7) fuel injectors.
The Holley LS1/2/6 Lo-Ram manifold kits are designed for Gen III and IV LS engines equipped with cathedral-port cylinder heads.
Part Number 300-620 is a top-feed plenum entry configuration that is designed to allow the currently available Hi-Ram 105 mm plenum tops to be fitted to a low-profile base intake manifold. The short runner, low-profile base intake manifold intended for forced induction applications was conceived to package with an air-to-water plenum-mounted intercooler with a shorter overall height than possible with other existing intake manifolds. Using a modular design, the top-feed plenum configuration with a 105mm top keeps the overall height at just 9.07 inches.

The Lo-Ram intake manifolds are designed for forced-induction engines, and the 105mm throttle body (part number 112-581 or similar models). The base intake manifold is designed with a lower overall height to fit under a stock or mildly modified hood in the front-feed configuration.
Part number 300-621 is a front-feed configuration designed with a lower overall height to fit under a stock or mildly modified hood in the front-feed configuration. It will clear a fourth-generation Camaro and C5 Corvette cowl without modification. The front-entry plenum allows the design and fabrication of special throttle body adapters and/or inlet ducts for custom installations. The high-volume fuel rails utilize 8 AN O-ring ports and include mounting hardware. Overall height with the 105mm throttle body adapter is 6.86 inches.
If you’re looking for either a traditional or modern appearing EFI setup, it time you take a look at what Holley Performance Products has delivered to enthusiasts who want a great EFI system and one that looks as good as it performs.