I am not planning a lot in terms of power boosts for my 1949 Plymouth. Shaving the head (or something else) shall be the first step. And then end of next year a dual carb set-up will be on the agenda. In regard to the "head shaving" matter: What brings the best performance boost shaving the head of an actual 218 engine or exchanging the head with a 230 head (I believe they should fit my engine).   thanks for your insights