#6 Check Valve Spring 90-250 Pound Range

The ENDERLE #6 Check Valve Spring in the 90–250 pound range is a precision-engineered pressure regulation component designed for fuel system applications requiring reliable, repeatable cracking pressure control. This steel check valve spring maintains consistent back-pressure across the 90–250 psi operating window, making it essential for carburetor systems, fuel injection tuning, and high-performance engine builds where pressure stability directly affects fuel atomization and combustion efficiency.

Built to ENDERLE's OEM standards, this spring component features steel construction sized for 6 AN (six-line) fuel system fittings, a common specification in racing and restoration work. The 90–250 psi pressure range indicates the spring's load curve—a wider band that accommodates tuning variations without requiring spring swaps. Individual replacement springs allow builders to fine-tune fuel pressure without overhauling entire manifold assemblies, reducing downtime and diagnostic costs during carburetor calibration or fuel system troubleshooting. Compact dimensions (1.85 × 0.65 × 2.95 inches) and minimal weight (0.01 lbs) ensure direct bolt-in fitment in OEM and custom fuel rail configurations.

This component is specified for classic fuel system restoration, street rod builds, vintage racing platforms, and modern carbureted engines where precision pressure control impacts performance and fuel economy. Buyers familiar with ENDERLE fuel systems recognize that spring selection is critical to matching fuel delivery to engine displacement and carburetor demand—undersized springs cause flooding; oversized springs starve the engine under load.

ENDERLE has engineered fuel system components for decades, and individual check valve springs remain core service parts for any serious carburetor tuner or restoration shop. This specific 90–250 range spring is a stock replacement, not a performance upgrade—authenticity and compatibility with original ENDERLE manifolds make it the correct choice for period-correct restoration and maintenance.