GReddy’s e-Manage is a cost effective programmable engine management system that allows you to properly tune your factory engine control without having to change the entire factory ECU system to an expensive "stand-alone" unit or the inconvenience of sending it out for a full ECU reprogram. The e-Manage system is a true universal "piggy-back" type unit that taps into most Japanese factory ECU wiring, by utilizing the vehicle’s existing sensors (or optional upgraded sensors if factory sensors are maxed out). The major benefit is the factory ECU settings become your "Base-MAP" for tuning. There is no need for extensive tuning for normal driving conditions, but does allow the tuner to fine tune, adjust for injector changes, and add new MAP(s) for situations the factory ECU is not capable of (like on-boost conditions).
c&p'd from their site.
you don't need a manual boost controller.