4360 Flange Gasket

The Holley 4360 Flange Gasket (HLY108-25) is a precision carburetor base plate gasket engineered for 4-barrel spread bore carburetors. This composite gasket seals the critical interface between your carburetor body and intake manifold, preventing fuel and air leaks that compromise engine performance and fuel economy. Whether you're rebuilding a classic muscle car, restoring a street rod, or maintaining a performance engine, this gasket is essential for ensuring a clean, reliable seal that withstands heat cycling and manifold pressure.

Constructed from durable composite material with a nominal thickness of 0.063 inches, the 4360 Flange Gasket is designed specifically for Holley 4-barrel carburetors with spread bore (non-square bore) configuration and features four mounting holes for secure fastening. The composite construction resists fuel, oil, and coolant exposure while maintaining dimensional stability across repeated thermal cycles—critical for street and strip applications. This gasket's engineered thickness and material formulation prevent blow-out under boost or high-RPM conditions while maintaining a low-profile fit that doesn't compromise carburetor-to-manifold clearance.

Professional mechanics and performance enthusiasts trust Holley gaskets as OEM-quality replacements during carburetor overhauls, intake manifold work, or carb swaps. Installation is straightforward: position the gasket on the manifold studs, align the four holes with your carburetor's base, and torque fasteners to manufacturer spec in a star pattern. Weighing just 0.2 lbs and measuring 6.95 x 8.9 inches, this gasket fits standard Holley 4360 applications. Always replace this gasket during any carb removal to prevent fuel seepage and ensure proper air-fuel delivery—it's an inexpensive insurance policy against vacuum leaks and performance loss.