displacement is charged by taxes. 3.8 is really to much...the 3.2 is the magic number. so far can i go with my economics, and a mechanics specialist in a tuning magazine told me that the MB 3.2 engine is one of the best base's for tuning. The 3.2 engine which uses AMG for its 32AMG cars (C 32amg and slk 32amg). I think it is the same engine in the clk 320 i think...is it??