Tech Tips
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Engine Preparation A. Clean flat surfaces are essential to seal any performance engine. A residue-free solvent such as aerosol brake cleaner should be used on the block and head sealing surfaces prior to assembly. B. ICS Titan head gaskets (S prefix) have unique patented combustion seals and coolant seals, these gaskets are for engines without O-rings in the block or head and are designed to be used without additional sealants. However, many engine builders use a light spray of KW Copper Coat (available here) for additional insurance against coolant leaks. ICS Titan head gaskets should always be re-torqued after 1 complete heat cycle (cold, to running temp, to cold). E. O-Rings in the block or cylinder head are required for combustion sealing when using Pro Copper (P prefix) or Titan (T prefix) head gaskets. ICS Titan (S prefix) head gaskets do not require O-rings in the block or heads. SCE sells stainless steel O-Ring wire in a kit to do one V-8 engine or spools for the engine builder. SCE stainless steel O-Ring wire is preferred over copper wire that can flatten or dent to form a leak path. F. O-Rings may be installed in either the block or cylinder head, combustion sealing is not affected by placement. However, when using aluminum cylinder heads it is preferable to place the O-rings in the cylinder head to prevent friction brinneling (indentation) of the aluminum sealing surface. When using copper head gaskets thinner than .050, O-ring height should be no more than 25% of gasket thickness. For instance: the proper dimensions for the O-ring groove with an .043 thick gasket using .041 wire would be; .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. G. In extreme racing engines when receiver grooves are necessary, alignment of O-Ring and receiver groove is critical, as is the depth and width of the receiver groove in relation to the height & width of the wire. With a receiver groove setup, since we have someplace for the gasket to be displaced (the groove), the height of the O-ring is limited only by the wire diameter (at least 50% of the wire must be below the surface for the wire to be retained in the groove). To form a strong combustion seal, the depth and width of the receiver groove must be properly related to the wire protrusion and width. Use these ratios: receiver groove depth should be 75% of the O-ring protrusion and the receiver groove width should be 1.5 times the wire width. H. 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. SCE provides an O-Ring installation kit, (SCE PART #31542) 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. The steps to O-ring your engine may seem like a lot of extra hassle but it is no more difficult than degreeing a cam and every bit as important. Plus, once the O-ring setup is completed you will have a serviceable, bulletproof head gasket seal. I. Racing engine head gaskets should be re-torqued after initial run-in regardless of type, solid copper, MLS 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. J. SCE Pro Copper (P prefix) and Titan (T prefix) head gaskets can be reused 4 to 5 times simply by cleaning with a residue-free solvent such as aerosol brake cleaner and applying KW Copper Coat for coolant sealing . ICS Titan(S prefix) head gasket are not recommended for re-use. DO NOT use a torch or household oven to re-anneal copper gaskets, at the temperature required to anneal copper the metal will oxidize (turn black) and begin to scale. The annealing process requires special oxygen-free vacuum ovens to achieve satisfactory results. |
