Also ckeck the Throttle body and compair to a usdm one and the t-stat housing neck might have 2 holes compaired to a usdm one with 3(for the bvsv) and like someone else said see if their is a EGR but really the person could have swamped all of this stuff.
Also make sure the motor has low miles like all of the JDM motors...
J/K.