The rear cylinders tend to get more air and run leaner than the others. This combined getting hot coolant preheated by the other cylinders means that they hold back the rest of the engine from being tuned to its potential.
"Capitalization is the difference between helping your Uncle Jack off a horse, and helping your uncle jack off a horse." "'she' also likes to swap since I think I am going to need to give her to woody again." - Dvlhntr "full alphabetic boost mode" - ChristopherTheOne " Purrs like a sexually satisfied black panther." - BigTDogg "Two oil eating, angry, spinning triangles of death." - turtleboy on rotary engines