Sinister Diesel Adjustable Blue Spring Fuel Pressure Kit for Ford F-250/F-350/Excursion 2003-2007 (6.0L)

Fits 2003-2007 Ford F-250/F-350 Super Duty and 2003-2005 Excursion (6.0L). Not compatible with E-series models.

The Sinister Diesel Adjustable Blue Spring Kit (SD-FUELBLK-6.0-ADJ) is a critical upgrade for the 6.0L Powerstroke fuel system. By replacing the weak factory regulator spring with the updated "Blue Spring," this kit restores fuel pressure—typically providing an increase of 10 psi—to ensure injectors remain properly lubricated and cooled. Maintaining adequate pressure prevents injector cavitation, which is a leading cause of premature failure in Powerstroke engines.

Unlike standard kits, this version includes a CNC-machined T6-6061 billet aluminum housing. This component replaces the prone-to-leak factory cast aluminum housing and features an integrated adjustment screw. This allows you to fine-tune fuel pressure between 55-68 psi to suit your specific performance needs or to compensate for spring settling over time. The housing is finished in signature Sinister Blue anodizing for corrosion resistance and a clean look under the hood.

• Material: CNC Machined T6-6061 billet aluminum housing
• Adjustment Range: User-adjustable for 55-68 psi
• Finish: Anodized Sinister Blue with laser-etched logo
• Function: Restores lost fuel pressure and protects injectors from low-pressure damage
• Installation: Simple 30-minute bolt-on installation
• Manufacturer Part Number: SD-FUELBLK-6.0-ADJ

Includes: (1) Sinister Diesel Billet Spring Housing, (1) Updated Blue Spring, (1) Complete Gasket and O-ring set, and all necessary installation hardware.