How hot would the Colossal Titan's temperature be?
Found by googling "attack on titan temperature", from Kūsō Kagaku Dokuhon (空想科学読本, literally “fantasy science reader”) is a series that addresses, queries and explains the science behind popular Japanese anime and manga:


  A 60 metre high Titan would have a body temperature of 602 degrees.


You can buy the source in Japanese on Amazon.