Fuelab 51505-4-L-E Series EFI Adjustable Fuel Pressure Regulator Large Seat - 515

The Fuelab 51505-4-L-E is part of the 515 Series Adjustable Fuel Pressure Regulator lineup, engineered for high-performance EFI applications. Built with a large seat configuration, this regulator delivers precise, stable fuel pressure control across a wide operating range—from carbureted applications starting at 1 PSID up to fuel injected applications at 125 PSID. The 515 Series is designed with versatility in mind, accepting both port-style and non-port-style union fittings without interference.

Constructed from billet aluminum with a military-spec anodize finish (MIL-A-8625, Type II), this regulator is built to withstand demanding performance environments while maintaining a clean, professional appearance. The -6AN return port is conveniently located on the bottom of the unit for clean plumbing routing.

Key Features:

• EFI-rated large seat for high-flow fuel delivery
• Two -6AN or -10AN inlet ports and one -6AN return port
• Compatible with gasoline, diesel, methanol, and ethanol fuels
• Billet aluminum body with military-spec anodize (MIL-A-8625, Type II)
• Fine thread pitch adjustment for precise pressure tuning
• Includes versatile mounting bracket and stainless steel hardware
• 1/8 NPT gauge port with plug for external fuel pressure gauge
• 1/8 NPT pressure reference port with barbed fitting for MAP sensor or vacuum reference
• Backed by a 2-year limited warranty

The Fuelab 515 Series fuel pressure regulator is an ideal choice for performance EFI builds requiring reliable, adjustable fuel pressure regulation with multi-fuel compatibility and a durable, race-proven construction.