Understanding Nitrous Purge Line Systems in Vehicles

Understanding Nitrous Purge Lines

Nitrous oxide systems are becoming increasingly popular modifications for vehicles seeking a power boost. Nitrous oxide, commonly known as "nitrous," delivers more oxygen to your engine, allowing for increased combustion and horsepower output. However, properly installing a nitrous system requires an understanding of components like the nitrous purge line.

What is a Nitrous Purge Line?

A nitrous purge line is a component on nitrous oxide injection systems. It serves an important safety purpose. The nitrous purge line provides an alternate path for nitrous oxide to escape when the system is activated but fuel is not present. This prevents engine damage from nitrous oxide entering the engine without fuel to combust it.

Why Do You Need a Purge Line?

When you activate your nitrous system, both nitrous oxide and extra fuel are injected into the engine. The two combine to create a bigger explosion in the combustion chamber, generating more horsepower. However, if nitrous enters the engine when fuel is not present, the oxygen can lead to excessive heat buildup, resulting in expensive engine damage.

The nitrous purge line prevents this by giving the extra nitrous oxide a place to safely vent out of the system. When you arm a nitrous system, it first flows nitrous through the purge line to remove any air bubbles. This ensures the line is full of nitrous oxide. Then, when you activate the system, any nitrous that enters the engine will immediately combine with the extra fuel being injected.

How Does a Nitrous Purge Work?

A nitrous purge line installs between the nitrous solenoid and the engine intake manifold. When you arm your nitrous system, the electric solenoid first opens, allowing high pressure nitrous oxide to flow from the nitrous bottle through the purge line. This serves multiple purposes:

• It removes any debris that may have entered the line.
• It eliminates air bubbles, fully packing the line with nitrous.
• It allows you to verify nitrous flow before activating the system.

Once the line fills, the nitrous solenoid closes. This stops the flow to the purge line and redirects it to the engine intake when the system is triggered. The purge line remains packed with high pressure nitrous oxide until you deactivate the arm switch.

Installing a Nitrous Purge Line

Properly installing the nitrous purge line is critical for system safety and performance. Here are key steps to take:

Mount the Nitrous Solenoid

Start by securely mounting your nitrous solenoid near the back of the engine bay. Ensure all ports and fittings are accessible and install the component to manufacturer specifications.

Determine Purge Line Mounting Location

Decide on an appropriate place to mount the purge line outlet. This should direct purged nitrous gas safely out of the engine bay to atmosphere. Common mounting locations include holes in the hood, fender area, or bumper cover. Choose a position away from engine wiring, belts, and linkages.

Install Purge Line Outlet Fitting

Apply thread sealant to the purge line outlet fitting if required. Install it in the selected mounting hole for the purge line exit. Ensure a tight, leak-free fitment.

Cut Purge Line to Length

Measure from the outlet on the back of your nitrous solenoid to the installed purge line outlet fitting. Cut your purge line tubing to this length using a tubing cutter or razor knife. Ensure cleanly cut square edges to promote leak-free connections.

Install Purge Line on Solenoid

Apply thread sealant if needed to the purge outlet fitting on your nitrous solenoid. Install one end of the cut purge line into this outlet, tightening securely. Then connect the other end to the installed purge line exit fitting. Again tighten all connections securely while being careful not to twist or kink the line.

Once installed, briefly activate the system to verify smooth nitrous flow from the solenoid through the purge line for venting. Your system is now ready to power up!

Maintaining Your Nitrous Purge System

Like all components on a nitrous system, performing proper maintenance is critical for safety and performance. Here are key purge line maintenance tips:

Inspect Lines and Fittings

Periodically inspect all purge line fittings for leaks and damage. Look for discoloration from leaks as well as kinks or cuts in the lines themselves. Damaged purge line components can prevent safe system operation.

Replace Damaged Parts

Do not attempt to repair damaged purge lines or fittings. The extreme high-pressure nitrous flowing through them makes minor defects risky. Instead, replace any damaged purge components with factory parts rated specifically for nitrous systems.

Check Route for Issues

Inspect the purge line routing for problems. Ensure the outlet still vents nitrous safely away from engine components out of the bay. Check for rubbing or chafing against hot exhaust components or moving parts like fan belts. Correct any issues immediately.

Activate Periodically

Briefly activate your nitrous system occasionally even if not spraying nitrous into your engine. Cycling nitrous through the purge line helps maintain the system and ensures smooth flow when you need that power boost!

Installing and maintaining a nitrous purge line is critical for system safety. Follow these guidelines when plumbing your nitrous oxide system to enjoy safe and reliable power gains!

FAQs

What psi should my nitrous purge line handle?

Nitrous purge lines and fittings should be rated for at least 1000 psi working pressure. Nitrous bottles are pressurized up to 950 psi when full, making high pressure capacity critical.

Where does the nitrous purge line vent to?

The nitrous purge line outlet should vent completely out of the engine bay, often routing through holes in the hood, fenderwell, or bumper. This safely vents pressurized nitrous gas to atmosphere away from engine heat sources.

Why does air come out when I first activate my nitrous system?

Small amounts of air venting at first is normal and why the purge line exists. Upon arming, it packs the line with nitrous, which can take a few seconds depending on length. This guarantees nitrous and not air enters the engine.

How often should I purge my nitrous lines?

You should activate the purge cycle for a few seconds prior to using your nitrous system after long periods of inactivity. This maintains fresh nitrous in the lines and confirms proper working pressure for safety.