Agreed here. Air is a great insulator. Plus we're not talking about drastically different turbo locations (save for the GT47 "where my AC compressor goes" mount). So what if the block is seeing 2-300* air on the outside. It's seeing 1600-1800* air on the inside. Plus the block temp is regulated anyways. If you had a water-cooled brake master cylinder, that shit wouldn't melt either.