Lots of options here.
The SRT-4 set a land speed record for four-cylinder cars. F20C had the highest N/A specific output (240 horse from 2.0L). 4G63T sets records every other day.
The Ford Model T engine was built with no major change from 1908 to 1941. Think about that for a minute.
I am partial to and very impressed by the EJ22/25T. Boxers kick ass :tup: