If your replacing gaskets in the upper end you will want to consider replacing the LIM (Lower Intake Manifold) Gaskets as well. Factory GM Gaskets were plastic with rubber seals, they give out and cause problems over time. Replace them with the Felpro "Problem Solver" Gasket set (MS 98014 T) make sure you get ones with the T in it, they will be metal with rubber seals and much MUCH better quality.

Also Felpro or AcDelco supercharger gaskets, Garlocks are commonly referred to as Garleaks, again quality items recommended.

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