Originally Posted by Billy

Air in the intercooler never touches the turbo. Air passes through the turbo then into the intercooler, it has nothing to do with controlling boost. The only reason you might see differences with a FMIC like Zate explained is because you now have alot bigger intercooler core to fill as well as the extra piping to fill, all before anything gets to the engine. That's why you can experience a greater pressure drop with a larger intercooler.