This pressure relief valve is the ideal bypass valve for use with a positive displacement fuel pump (typically not required for diaphragm type pumps). For use with any carbureted race engine using a belt drive fuel pump. This bypass valve is well suited for alcohol carburetors with gear type pumps.

Adjustable diaphragm lets you set fuel pressure while the Holley jet inside allows you to reduce idle fuel pressure without affecting operating pressure. Due to fuel pump variations, the jet is not included. The fuel pump relief valve features a stainless steel seat and bronze popitt valve for maximum resistance to corrosion.

• Easily mounts directly to the carb fuel log
• Adjusting screw on top sets high RPM fuel pressure
• Easy pressure adjustments at 7-14 PSI
• Adjustable to vastly different fuel pumps
• Maximum fuel availability at the carb
• 3/8" NPT ports

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1. The bypass is tapped for a Holley jet to reduce fuel pressure at idle. In most alcohol applications this can be plugged or run with a small jet. With gasoline, you can reduce the idle fuel pressure by installing progressively larger jets. The condition and type of fuel pump will determine the jet size.
2. Make sure to install a jet or plug. A plug can be easily made by plugging the hole in an old jet with a small screw or solder.