The Muscle Car and Street Rod Engine Oils from COMP Cams are specifically designed to be used in engines that experience extended periods of storage. The oils utilize a blended synthetic formula fully approved for use in engines originally equipped with mineral oil. They provide all the benefits of mineral oil without the unwanted extras that lead to rust and corrosion. Designed for regular use, these oils will not create sludge, varnish or choke internal engine surfaces, and they are compatible with all gaskets and seals.