All cranks are stamped fte all heads are the.same just later uk ones have a waterway blocked and a 4efte block has 3 holes around.the oil filter area instead of one bug thingy in the middle. Fte pistons are dished 5efe pistons are nearly flat, fhe pistons have abit of a bump and 4efe pistons have a huge bump. 4efe conrods are skinny- but so are glanza conrods. Designed to bend, not break