The opposite of a thin block. Thin 1275 Blocks seen on the early cars and pictured in some tuning books and S&M by Horler. Weslake-Monza 1330 In a message dated 02/10/2009 01:35:14 GMT Daylight Time, grunthaner at gmail.com writes: Herb & List, What is a thick block I never heard of that term before. Lin