By installing an intake gasket made of 3mm thick heat-resistant resin Bakelite material between the intake port of the engine body and the intake manifold, you can expect a 3-5% increase in power due to a decrease in intake temperature! It blocks the heat transmitted from the cylinder head to the intake manifold and prevents the metal intake manifold from becoming a heat sink. As a result, it prevents the intake air filling temperature from increasing and improves filling efficiency. A decrease in intake temperature leads to a 3-5% increase in power. Two genuine gaskets are required for installation.
It is introduced on Ameblo's "M&M HONDA's Honda Honki."
https://ameblo.jp/mandm-honda/entry-11436099809.html