Is silicone sealer required on the copper 2V adapters for the Ford 351C/400M headers?

As you may already know, all of our headers for the Ford 351C (Cleveland), 351M, and 400 engines are made with the 4V (four barrel) flange for the larger port cylinder heads. If you are using 2V (two barrel) cylinder heads you will need our copper adapters

A common question asked is whether silicone sealer is required when using these adapters?

Yes, you need to use Permatex sealer on BOTH sides of the copper adapters - unless you anneal the adapters!

Annealing the adapters is a heating/cooling process that with copper makes the material slightly softer. Most DIY (do-it-yourself) builders do not have access to an oven or balanced heat source that will properly heat the gasket. You can perform a Google search online for more information on annealing gaskets and what is involved.