When stepping up to performance cylinder head gaskets, your first order of business will be choosing the gasket material best suited for your application. See our How to Choose the Right Gasket post for a quick reference as to which material makes the most sense for you.
Because of its durability, copper gaskets are commonly used on high performance street/strip engines. Copper provides good resistance to blowouts because copper naturally conducts and distributes heat evenly, which minimizes warping and allows for a strong seal even on rough or damaged surfaces.
Because copper is often the head gasket material of choice for high performance applications, we focused on it for this quick guide to installing head gaskets:
1. Clean flat surfaces are essential to seal any performance engine. A solvent such as brake cleaner should be used on the block and head prior to assembly.
2. To seal around water and oil passages, we recommend an anaerobic sealer like SCE’s Copper Coat. Always allow the sealant to tack up for 15 to 20 minutes before assembly.
3. O-rings are generally required to make a copper gasket system work to potential. O-ring wire kits are available for one V-8 engine, or in entire spools for engine builders. Stainless steel O-ring wire is preferred over copper wire which can flatten or dent, and form leak paths.
4. O-ring grooves may be cut in either the block or cylinder head. When using copper head gaskets thinner than .050, O-ring height should be no more than 25 percent of gasket thickness. For instance, the proper dimensions for an .043 thick gasket using .041 wire would be; a .038 to .040 groove width (provides a .001 interference fit), and a .032 groove depth (leaves .008-.010 of the wire protruding above the deck). This machining can be done at most high performance machine shops.
5. When receiver grooves are necessary, alignment of O-ring and receiver groove is critical, as is the depth and width of the receiver groove. Receiver groove depth should generally be 75 percent of the O-ring protrusion, and the receiver groove should be 1.5 times the wire width. Example: If the O-ring is .041 wide and .015 above the deck; receiver groove should be .012 deep and .060 wide.
6. While the machining of O-ring and receiver grooves must be done by a machinist, the installation of the O-ring wire can be done by anyone, using common hand tools. When tapping O-ring wire into the groove, use care to avoid denting the wire. Our friends at SCE provide an O-ring installation kit which includes instructions, an installation tool and O-ring wire. When cutting stainless O-ring wire, file the ends square to provide the tightest possible seal.
7. Head gaskets should be re-torqued after initial run-in regardless of type, solid copper or composition. SCE recommends using factory torque specs. Do not over torque. Allow the heads and block to cool for accurate torque readings. Always use a torque wrench and have it calibrated often. Premium-grade head bolts or studs, with hardened washers, are recommended.
8. SCE copper gaskets can be reused four to five times simply by cleaning in common solvent. DO NOT use a torch or household oven to re-anneal copper gaskets. The annealing process requires special vacuum ovens to achieve satisfactory results.
These installation tips may seem like a lot of information for head gaskets; however, installing a copper head gasket and O-ring system is really easier than degreeing a cam—and just as important.