[MikeK]

Glyptal adds a layer of thermal insulation between the block and the oil. Considering the great mass difference between the block and the oil, this leaves the oil returning to the pan relatively cooler and the block HOT AS HELL. Just what you need in a model A; oil that doesn't get hot enough to evaporate condensation, acids, and other blowby junk, and another way to keep heat in a block with a primitive cooling system. It looks pretty though, and covers minor cracks and other uglies a rebuilder wants to hide. A foole and his $80 are soon parted???