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You bought a Hellcat for one reason: raw, unadulterated power. Whether you’re piloting a Challenger or a Charger, that supercharged 6.2L HEMI is a masterpiece of American engineering. But in the world of modern muscle, "enough" is a word we don't use. If you’re looking to shave seconds off your quarter-mile or simply want that neck-snapping kick that only chemical forced induction can provide, it’s time to talk about nitrous.

This hellcat nitrous system installation guide is designed for the enthusiast who isn't afraid to get their hands dirty. We’re moving past the basics and diving into the precision work required to safely add 50 to 300+ horsepower to your Mopar.

Push the limits. Build for speed. Shop with confidence at DTX Performance.

Select Your System: Plate vs. Lid

Before you pick up a wrench, you need to choose your delivery method. For the Hellcat platform, you have two primary high-performance options:

1. Billet Plate Systems: These are the most common and cost-effective. A precision-machined aluminum plate bolts directly between your throttle body and the intake snout. It’s a clean, effective way to introduce the "juice" into the airflow.
2. Supercharger Lid Systems: If you’re chasing maximum efficiency and a "show-ready" engine bay, a nitrous lid is the gold standard. These replace the factory supercharger lid entirely. They feature internal spray bars or CNC-machined passages that ensure perfectly even distribution to every cylinder.

Regardless of your choice, ensure your kit includes high-flow solenoids and stainless steel braided lines. Excellence is in the details.

Gear Up: Tools for the Job

Precision requires the right equipment. Don’t settle for "close enough" when working on a high-output engine. You’ll need a dedicated workspace and a few specific tools to complete the installation safely and efficiently.

• Quick-Release Fuel Line Tool: Essential for tapping into the factory fuel system without damaging the connectors.
• Metric Socket Set: Deep and shallow sockets for throttle body and lid bolts.
• Open-End Wrenches: Specifically for tightening AN fittings on your nitrous and fuel lines.
• Wire Strippers and Crimpers: For a professional-grade electrical install.
• Drill and Bits: For mounting the bottle brackets and potentially the interior switches.

Step 1: Mount the Nitrous Bottle

Every high-performance journey starts in the trunk. The placement of your nitrous bottle is critical for consistent pressure and flow.

1. Positioning: Mount the bottle at a 45-degree angle with the valve facing the front of the vehicle. This ensures the internal siphon tube is always submerged in liquid nitrous during hard acceleration.
2. Secure the Brackets: Use the provided heavy-duty brackets. Drill through the trunk floor, ensuring you aren't hitting the fuel tank or electrical looms. Bolt them down tight.
3. Run the Main Line: Feed the main -6AN or -4AN nitrous line from the trunk to the engine bay. Follow the factory fuel or brake lines under the car, securing the line with P-clamps every 12-18 inches. Avoid heat sources like the exhaust and moving parts like the driveshaft.

Step 2: Install the Plate or Lid

Now, we move to the heart of the beast.

For a Plate System:

1. Remove the air intake tube from the throttle body.
2. Unbolt the throttle body from the supercharger snout.
3. Place the billet nitrous plate between the snout and the throttle body. Use the longer hardware typically provided in your kit. Ensure the "Nitrous" and "Fuel" ports are easily accessible for line routing.
4. Reinstall the throttle body and torque to factory specs.

For a Lid System:

1. Relieve fuel pressure and disconnect the MAP sensor and other electrical connectors on the factory lid.
2. Remove the bolts securing the factory supercharger lid.
3. Carefully lift the factory lid off. Ensure no debris enters the intercooler bricks.
4. Seat your new performance nitrous lid. Bolt it down in the factory sequence to ensure an even seal.

Step 3: Tapping the Fuel Supply

Nitrous is only half the equation. To prevent a catastrophic lean condition, you must provide extra fuel.

1. Locate the Fuel Rail: On the Hellcat, you’ll find the fuel supply line at the rear of the engine.
2. The Tap: Most modern kits include a "fuel rail adapter." This piece installs between the factory fuel line and the rail, providing a 1/8 NPT or -4AN port for your fuel solenoid.
3. No Cutting Required: We recommend kits that utilize these adapters to maintain the integrity of your factory lines. If your kit requires cutting, ensure you use high-pressure EFI-rated hose clamps and T-fittings.

Step 4: Mounting and Plumbing Solenoids

Your solenoids are the gatekeepers of power. They need to be mounted securely and as close to the injection point as possible to minimize "lag."

1. Mounting: Use a dedicated solenoid bracket. Many Hellcat-specific kits mount these directly to the thermostat housing or the side of the supercharger.
2. Connect the Lines: Run the short stainless lines from the solenoids to the plate or lid.
   • Blue Line/Fitting: Nitrous.
   • Red Line/Fitting: Fuel.
3. Tighten with Care: AN fittings do not require thread tape. They seal on the flare. Tighten them hand-tight plus a quarter turn with a wrench. Over-tightening can crack the flare.

Step 5: The Electrical Brain

A nitrous system is only as safe as its wiring. You want multiple "checks" in place before the system activates.

1. The Relay: Never wire your solenoids directly to a switch. Use a 40-amp relay. This ensures the high-draw solenoids get clean power directly from the battery/terminal block.
2. WOT (Wide Open Throttle) Switch: This is your primary safety. The system should only engage when your foot is floored. On modern Hellcats, this is usually an electronic signal tapped from the accelerator pedal position (APP) sensor.
3. Arming Switch: Mount this in the cabin. This allows you to "turn on" the system’s ability to fire.
4. The Purge: Install a purge solenoid to clear air from the lines. It ensures that when you hit the throttle, you get instant liquid nitrous, not a pocket of air that causes a stumble. Route the purge tube to vent out of the hood scoop or cowl for that classic look.

Step 6: Jetting for Power

Precision is everything. The "shot" size is determined by the small brass jets you insert into the plate or lid fittings.

• Start Small: If you’re on a stock tune and stock fuel pumps, start with a 50hp or 75hp shot.
• The Ratio: Follow the manufacturer’s jetting chart religiously. The balance between the nitrous jet and the fuel jet determines your Air/Fuel ratio.
• Shop Excellence: Need more fuel? Check out our high-performance fuel injectors to support higher horsepower levels.

Safety Tips and Pro-Level Upgrades

You’re playing with fire, literally. Treat your nitrous system with respect.

• Wideband O2 Gauge: This is non-negotiable. You need to see your Air/Fuel ratio in real-time. If it leans out, let off the throttle immediately.
• Bottle Heater: Nitrous pressure is temperature-dependent. For a consistent hit, you want your bottle pressure between 900-1050 PSI. A bottle heater keeps you in the sweet spot.
• Window Switch: This electronic device ensures the nitrous only sprays within a specific RPM window (e.g., 3,000 RPM to 6,000 RPM). This prevents spraying into the rev limiter or at too low of an RPM where backfires occur.

Final Checks and The First Hit

Before you head to the track, do a "dry run."

1. Leak Test: With the bottle off, arm the system and trigger the WOT switch (engine off!). Listen for the solenoids to "click."
2. Pressure Test: Open the bottle valve slowly. Check every fitting for the tell-tale frost or hiss of a leak.
3. The Purge: Tap the purge button. You should see a clean white cloud.
4. The Hit: Go to a safe, closed course. Ensure your tires are warm. In 2nd or 3rd gear, roll into the throttle. When the system hits, be ready: the Hellcat becomes a different animal entirely.

Building a world-class muscle car requires world-class parts. From brake upgrades to handle that new speed, to the best induction systems on the market, DTX Performance has your back.

Push harder. Drive faster. Build with DTX.