EVIL ENERGY Fuel Pressure Regulator 6AN EFI Bypass Return — Red Anodized, Adjustable 30–70 PSI with Gauge & Kit

The EVIL ENERGY 6AN EFI bypass return fuel pressure regulator is an adjustable gasoline/E85-compatible regulator that lets you set fuel pressure between 30 and 70 PSI for precise EFI tuning.

This compact, anodized-red regulator is built for aftermarket EFI systems and comes as a complete kit with fittings, a pressure gauge, a mounting bracket and stainless braided fuel line. It supports gasoline and alcohol blends (E85) and installs in bypass/return-style fuel systems to stabilize pressure for high-performance or modified engines. The regulator’s top-mounted adjustment screw and included gauge make tuning straightforward while multiple included adapters speed installation to many fuel rails.

How do I adjust the fuel pressure and read the gauge?

Adjustment is done via the set screw on the regulator’s top; turn to increase or decrease pressure and monitor the included gauge to reach your target PSI. Make fine changes with the engine idling and verify under load, if possible, to confirm consistent pressure across operating conditions.

• Adjustment range: 30–70 PSI
• Top-mounted set screw for simple tuning
• Included pressure gauge for immediate feedback
• Use thread sealant tape on the NPT gauge port to prevent leaks

Will this regulator work with my fuel type and setup?

The EVIL ENERGY regulator is compatible with gasoline and alcohol/ethanol blends such as E85, but it is not suitable for diesel. It’s designed for bypass/return EFI systems; using certain supplied fittings incorrectly (on the regulator instead of the fuel rail) may cause leaks.

• Compatible: gasoline and E85/alcohol blends
• Not compatible: diesel fuel
• Designed for bypass/return EFI installations
• Note: nylon-braided line is not compatible with E85

What fittings and parts are included in the package?

The kit arrives with multiple AN and ORB fittings, braided fuel line and mounting hardware so you can adapt the regulator to many fuel rail interfaces. Pay attention to the supplied 6AN-to-M fittings — they are intended for fuel rail use only and should not be installed directly on the regulator body.

• 1x EVIL ENERGY fuel pressure regulator (red anodized)
• 1x pressure gauge and 1x mounting bracket
• Various fittings: AN6 plugs, ORB-to-AN6 fittings, AN6-to-M fittings
• 3x stainless braided CPE fuel lines for routing and connection

How do I avoid leaks and ensure a durable installation?

Use proper thread sealant tape on the NPT gauge port and follow the manufacturer’s guidance on which adapters belong on the fuel rail versus the regulator. Avoid installing incompatible fittings on the regulator body and inspect all hoses and clamps after the first run to confirm tight, leak-free connections.

• Seal NPT gauge port with thread sealant tape
• Do not install 6AN-to-M fittings on the regulator body
• Verify hoses and clamps after engine startup
• Use fuel-rated braided lines compatible with chosen fuel type

Who is this for: The EVIL ENERGY 6AN EFI Fuel Pressure Regulator is aimed at enthusiasts, tuners and mechanics running aftermarket EFI systems who need adjustable pressure control for modified engines, turbo or naturally aspirated setups, and those switching between gasoline and ethanol blends. It’s a good choice if you want a full-fitment kit with gauge and multiple adapters for flexible installation, but it’s not intended for diesel systems or setups that lack a return-style fuel loop.