Header Gskts Seal-4-Good SBM Rect Port 1.0x1.625

The Header Gskts Seal-4-Good SBM Rect Port 1.0x1.625 by Patriot Exhaust is a precision-engineered exhaust header gasket designed for Small Block Mopar applications. If you're rebuilding a classic Mopar engine or upgrading your exhaust manifold, these gaskets are essential for sealing the critical junction between your cylinder head and exhaust header. Without a properly sealed header gasket, you'll face exhaust leaks that compromise performance, increase underhood heat, and create an irritating exhaust smell under load.

These Seal-4-Good gaskets feature a multi-layered aluminum construction that resists thermal cycling, vibration, and the extreme heat cycling that occurs during engine operation—especially critical in headers where temperatures exceed 1,200°F. The rectangular port design measures 1.0 x 1.625 inches, matching factory Small Block Mopar port specifications precisely. This pair includes two gaskets (one per side), ensuring complete coverage across both cylinder head ports. The layered aluminum composition provides superior durability compared to composite gaskets, maintaining its seal integrity through countless heat cycles without degradation or blow-through.

Engine builders and restoration enthusiasts working with classic Mopar small blocks—including 318, 340, and 360 cubic-inch engines—rely on these gaskets for trouble-free header installation. Proper installation requires clean mating surfaces and even bolt torque across the header flange to prevent warping and gasket failure. The lightweight construction (0.47 lbs total) won't add unnecessary weight, while the compact dimensions ensure easy handling during engine bay assembly. For any Mopar enthusiast seeking OEM-quality header gaskets that deliver consistent sealing performance, the Patriot Exhaust Seal-4-Good gasket set delivers reliability without compromise.