The material the Chevrolet Intake Manifold Gasket includes metal and fiber components. It is because of this multi level approach to sealing the intake to the cylinder head that make it possible for the fuel delivery system to perform as expected on your Chevrolet.
The use of the metal and fibers in the intake manifold gaskets is why it can contain the pathways for the air to flow to the cylinders in a closed system even with the expansion of the intake and heads. This is just part of the way an engine operates. As the engine heats up, the metal components that make it up expand and the material including the Chevrolet intake manifold gasket have to have the characteristics in it so it can compensate for this slight movement.
The reason for the need to replace the intake manifold gasket on your Chevrolet engine is not generally from wear or the seal being blow. It is because either the head gasket is blow or the head has to come off for some reason. Since the heads are directly connected to the intake manifold, when the head is removed, it is advisable to also replace the intake manifold gasket. This is the best way to ensure the seal surrounding the contact points of the manifold are intact.
Just like all other seals, when replacing the intake manifold gasket, the old gasket material has to be completely removed from the contact points on the heads and the intake. This will make it possible for the new gasket to create a seal that will have no breaches in it so the amount of air the onboard computer allows for in this intake system on your Chevrolet to remain at a constant amount.