Collector Gasket 3-1/2in

The Mr. Gasket Collector Gasket 3-1/2in (MPN 1203) is a compressed fiber exhaust manifold gasket engineered for high-performance engine sealing. Built to 0.062-inch thickness with a 3.5-inch diameter, this three-bolt gasket delivers reliable compression and heat resistance in demanding engine compartment environments. The compressed fiber composition resists gasket creep and maintains a consistent seal across thermal cycling—critical for engines that see sustained operation or frequent temperature swings.

Specification-wise, the 0.062-inch thickness is precisely calibrated to match OEM flange tolerances while providing adequate material for proper clamping load distribution across the three bolt positions. The 3.5-inch diameter opening accommodates standard collector port configurations found in small-block and mid-sized V8 engines. Compressed fiber gaskets like this one resist exhaust gas bypass better than solid cork alternatives, particularly under the high-pressure pulse cycles that develop in tuned headers and performance manifold systems. Mr. Gasket's manufacturing standards ensure uniform density and consistent material properties, reducing the likelihood of premature failure or exhaust leakage.

This gasket is essential for hot rod builders, engine rebuilders, and automotive enthusiasts performing manifold-to-collector connections on engines that demand precision sealing. Whether you're assembling a street performance engine, completing a stock engine rebuild, or upgrading exhaust flow, a high-quality collector gasket prevents exhaust leaks that rob horsepower and create unwanted noise. Keeping a spare on hand during major engine work or header installation ensures you're not halted by a failed seal.