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1950-1990 Universal Carbureted V8 Moderate ⏱️ 4-6 hours

Holley Sniper EFI Conversion Guide

🛠️ Parts You'll Need

Holley Sniper EFI System View on Amazon →
~$1,050-$1,300
Aeromotive EFI Fuel Pump View on Amazon →
~$250
EFI Fuel Pressure Regulator View on Amazon →
~$85
O2 Sensor Weld Bung View on Amazon →
~$12

Why Ditch the Carb?

Carburetors are fine until they're not. Cold mornings mean pumping the pedal and praying. Hot days mean vapor lock. Altitude changes mean re-jetting. And forget passing emissions without lying to the smog tech.

The Holley Sniper EFI replaces your carb with a self-tuning throttle body. It learns your engine in 50 miles and adjusts fuel delivery in real time. No laptop required. No tuning required. It just works.

What You Get

- Self-learning ECU: Tunes itself as you drive - Touchscreen display: Built into the throttle body - Wideband O2 sensor: Real-time air/fuel monitoring - Cold start control: Fires up at 20°F or 100°F, doesn't care - Timing control: Optional distributor control for even better performance

Cost: $1,000-$1,300 depending on options. One-time investment that pays back in reliability and drivability.

Compatibility

Works with any carbureted V8: - Chevy small block/big block - Ford Windsor/Cleveland/FE - Mopar LA/B/RB - Pontiac/Oldsmobile/Buick

Requirements: - 40+ psi fuel pressure (you'll need an electric pump) - Return-style fuel system (or add a regulator with return) - 12V switched power and ground

Installation Steps

1. Remove the old carb - Drain fuel, disconnect linkage, unbolt carb from intake - Clean gasket surface thoroughly

2. Install Sniper throttle body - New gasket, bolt Sniper to intake (same 4-bolt pattern as carb) - Connect throttle cable and kickdown linkage

3. Wire the ECU - Switched 12V (ignition on/off) - Constant 12V (battery) - Ground to engine block - RPM signal (either coil negative or distributor)

4. Install fuel pump and regulator - Sniper needs 58 psi at the throttle body - Mount electric pump near tank, run -6 AN line to engine bay - Install inline filter and pressure regulator with return line

5. Install O2 sensor - Weld bung in exhaust collector (12-18" from head) - Sniper includes wideband sensor, screw it in

6. Power on and tune - Sniper boots up, asks a few questions (engine size, cam, etc.) - Fire it up, let it idle for 5 minutes - Drive for 50 miles while ECU learns

Common Mistakes

- Low fuel pressure: Sniper needs 58 psi. Old mechanical pumps max out at 7-9 psi. You MUST install an EFI-rated pump. - Return line: Sniper needs a return line to tank. If your car doesn't have one, add a regulator with return. - O2 sensor placement: Too close to head = false readings. Too far = slow response. Sweet spot is 12-18" from exhaust port.

What to Expect

First startup: It'll stumble and hunt for idle. Normal. Let it learn for 5 minutes.

After 50 miles: Throttle response is instant, idle is rock solid, and you can start the car in -10°F weather with zero pumping.

Your classic just became a daily driver.