AEM 25-305BK Universal High-Cap Adjustable Fuel Pressure Regulator

Vehicle Fitment

• Universal fit - adapts to virtually any EFI-equipped gasoline vehicle with return-style fuel system
• Not vehicle-specific; verify compatibility with fuel system setup before installation

Features

• High-capacity universal adjustable fuel pressure regulator for EFI systems
• Wide adjustment range from ~40 PSI up to ~130 PSI for high-flow applications
• Boost-dependent rising fuel pressure rate (1:1) ideal for forced induction vehicles
• Three -6 AN ORB O-ring style inlet ports (2 inlets, 1 return)
• Integrated 1/8" NPT gauge port for fuel pressure gauge or sensor pick-up
• Compatible with gasoline, alcohol, race fuel, and high-pressure pump setups
• CNC-machined from durable 6061-T6 billet aluminum with black anodized finish
• Easy-to-adjust set screw design stands up to repeated tuning adjustments

Specifications

• Part number: AEM 25-305BK
• Type: Universal adjustable fuel pressure regulator
• Fuel system compatibility: EFI-equipped gasoline engines
• Adjustment range: ~40-130 PSI
• Pressure response: boost-dependent rising rate (1:1)
• Inlet ports: 2x -6 AN (9/16"-18) ORB
• Return port: -6 AN (9/16"-18) ORB
• Gauge port: 1/8" NPT
• Vacuum port: 5 mm (3/16") hose barb
• Material: CNC-machined 6061-T6 billet aluminum
• Finish: Black anodized
• Weight: ~1 lb
• Legal status: legal for sale/use on emissions-controlled vehicles; does not affect emissions components
• Warranty: Manufacturer's limited warranty

Included Components

• 1x AEM universal adjustable fuel pressure regulator (25-305BK)
• Universal mounting bracket with hardware
• Easy-adjust set screw
• Installation instructions

Product Description

The AEM 25-305BK Universal High-Capacity Adjustable Fuel Pressure Regulator is a versatile performance component designed to support high-flow EFI fuel systems across a wide range of vehicles. Its extended adjustment range - from approximately **40 PSI to 130 PSI** - makes it ideal for boosted and high-output engines that require precise fuel pressure control under varying load conditions. The regulator's **boost-dependent rising pressure rate (1:1)** ensures that fuel pressure rises in step with boost, helping deliver consistent fuel delivery for improved engine response and performance.

Machined from durable **6061-T6 billet aluminum** with a protective black anodized finish, the 25-305BK features multiple -6 AN inlet and return ORB ports plus an integrated **1/8" NPT gauge port** for easy monitoring or sensor integration. Its universal design allows it to be adapted to virtually any EFI-equipped gasoline vehicle with a return-style fuel system, provided proper fitting and plumbing are used. The built-in vacuum port further allows dynamic fuel pressure adjustments based on engine load or boost. This regulator is legal for use on emissions-controlled vehicles because it does not alter emissions-related hardware, and it is built for racers and enthusiast tuners alike who demand reliable, adjustable fuel pressure performance.