engine side cover

engine side guard

engine side panel

left engine side guard

left engine side panel

left side engine compartment door

right side engine

engine compartment side

engine enclosure side panel

side lever engine

side valve engine

side-valve type engine

side-side method

side-side scheme

naturally-aspirated engine （NA engine）

programmable electronic engine control equipped engine

Auto Side member and side frame

deduce unknown side from known side

differences side-by-side