EVIL ENERGY 6AN Male to 3/8″ & 5/16″ Female EFI Quick-Disconnect Fuel Fittings

This configuration is useful for many custom fuel system projects where maintaining an existing factory-style connection is preferable to cutting the fuel line.

3/8-Inch vs. 5/16-Inch EFI Quick-Disconnect Fittings

These EVIL ENERGY adapters are offered for two different quick-connect tube sizes.

The 3/8-inch and 5/16-inch dimensions refer to the nominal outside diameter of the mating male quick-connect tube ends.

They do not describe the AN thread size or the inside diameter of the adapter.

Important: Quick-connect fittings must match the mating tube diameter and connector profile. Two fittings with the same nominal tube diameter are not necessarily interchangeable.

Precision 37-Degree AN Flare Connection

The -6AN male connection uses a 37-degree flare sealing surface.

When connected to a compatible female AN fitting, the mating flare surfaces create the seal.

The 9/16-18 UNF threads provide the clamping force needed to secure the connection.

Unlike tapered pipe threads, AN flare connections do not rely on thread sealant.

Installation tip: Do not apply PTFE tape or pipe-thread sealant to the 37-degree AN flare threads.

The quick-disconnect side uses a different sealing mechanism, typically involving an internal seal and mechanical retainer. Its sealing components must be compatible with the intended fluid.

Durable 6061-T6 Aluminum Construction

EVIL ENERGY manufactures these adapters from 6061-T6 aluminum alloy.

This material offers a favorable strength-to-weight ratio and good corrosion resistance for compatible automotive plumbing applications.

The quick-connect retaining mechanism is manufactured from plastic, allowing the adapter to engage compatible male EFI tube ends.

Inspect the retaining mechanism before installation and replace damaged fittings rather than attempting to reuse cracked or worn retainers.

Ideal for LS Engine Swaps and Aftermarket Fuel Rails

EVIL ENERGY EFI quick-disconnect adapters are useful for custom automotive fuel plumbing installations.

Common applications include:

• GM LS1, LS2, LS3, LS6, and LS-based engine swaps

• Chevrolet Camaro and Corvette fuel system modifications

• GM 5.3L and 6.0L truck engine swaps

• Ford Mustang aftermarket fuel line conversions

• Custom fuel rail connections

• Fuel pressure regulator installations

• Modified fuel supply and return lines

• Compatible transmission cooler plumbing

• Custom fuel pressure sensor installations

For additional technical information, see our 255LPH vs. 340LPH vs. 450LPH vs. 525LPH Fuel Pump Comparison.

EVIL ENERGY 6AN EFI Quick-Disconnect Fitting Specifications

The advertised pressure rating should not be interpreted as a rating for the complete fuel system or connected hose assembly. Verify the pressure limits of every component, including the quick-connect seal and retainer.

What Vehicles Do EVIL ENERGY 6AN Quick-Disconnect Fittings Fit?

These are universal aftermarket adapters rather than guaranteed direct-fit OEM replacement parts.

They may be used with compatible male EFI quick-connect tube ends on a variety of vehicles.

Fitment note: Compatibility depends on the actual male tube diameter, retaining bead geometry, connector profile, fuel pressure, and sealing requirements. Vehicle make and model alone cannot confirm fitment.

How to Install a 6AN EFI Quick-Disconnect Fuel Adapter

1. Relieve fuel system pressure according to the vehicle manufacturer’s instructions.

2. Disconnect the battery and work in a well-ventilated area away from ignition sources.

3. Identify whether the mating male EFI tube end is 3/8-inch or 5/16-inch.

4. Inspect the tube end for corrosion, damage, scratches, and deformation.

5. Verify that the quick-connect profile matches the EVIL ENERGY adapter.

6. Inspect the adapter’s retaining mechanism and internal seal.

7. Push the female quick-connect adapter onto the male tube end until the retainer engages.

8. Perform a gentle pull test to confirm the connection is locked.

9. Connect the male -6AN flare to a compatible female AN fitting.

10. Secure the fuel hose to prevent vibration, abrasion, and mechanical stress.

11. Prime the fuel system and inspect all connections for leakage before operating the vehicle.

Never force a quick-connect adapter onto an incompatible tube end.

Important Fuel System Safety Notes

• Do not assume E85 compatibility without confirmation of the internal seal materials.

• Do not use damaged plastic retainers.

• Do not apply thread sealant to AN flare connections.

• Do not exceed the rating of the lowest-rated component.

• Do not use these fittings for brake hydraulic systems without explicit manufacturer approval.

• Do not substitute them for high-pressure direct-injection fuel connections unless specifically approved.

Quick-Disconnect Adapter vs. Hardline Compression Adapter

If your vehicle already has a compatible male EFI quick-connect tube end, the quick-disconnect adapter may provide a simpler installation.

If you’re working with plain stainless steel or aluminum hardline without a compatible quick-connect end, a correctly rated compression adapter may be more appropriate.

Buy EVIL ENERGY 6AN EFI Quick-Disconnect Fuel Fittings at Pro Street Online

Simplify your next custom fuel system installation with EVIL ENERGY 6AN Male to 3/8-Inch and 5/16-Inch Female Quick-Disconnect Fuel Fittings.

Featuring 6061-T6 aluminum construction, precision 37-degree AN flare sealing, and convenient female EFI quick-connect connections, these adapters provide a practical solution for connecting compatible factory-style fuel lines to aftermarket AN plumbing.

Shop fuel system adapters, braided hoses, fuel rails, and performance components at Pro Street Online.