Ive got some questions about intake plenum sizes
 

Ive heard that your engine gets best power high and low end if your intake plenum is the same displacement as the ci of your engine. Say that you have a 350 ci engine, would you find the ci of your intake including the intake runners or only measure the plenum to get 350 ci? Also would you need a smaller plenum for a turbo applacation? if so how would you figure out what size of plenum you need?
-JT