I would like to use some form of Viton product as a form-in-place gasket material, or at least a gasket dressing. This would be used to replace the standard silicone-based material that we are now using to seal components on automobile engines, so the material will be in contact with hot engine oil and gasoline vapors. Can you recommend a specific material? I would like it to be a self-supporting paste if possible.
If you actually want to replace the gasket entirely, the only choice you have would be to use a silicone RTV sealant, most likely one of the high-temperature Permatex Silicone Form-A-Gasket products. These are available in most auto-parts stores such as NAPA , PEP Boys or AutoZone.
If you want to use a real gasket, you should use a gasket dressing such as Permatex Form-A-Gasket #2. This material must be used with a physical gasket.
The above suggestions would hold true for oil pans, rocker covers, etc., but NOT for head gaskets. For a head gasket, you must use the proper metallic head gasket and a gasket cement such as Permatex Copper Form-A-Gasket, which is a pressure sensitive material when dry and really acts to hold the gasket in place during assembly. Silicone RTV and gasket dressing should NOT be used on head gaskets.
Care should be taken with any gasket maker or dressing to minimize the opportunity for the gasket maker or dressing to squeeze out too much and get into the engine.