most external wastegates work exactly the same and all do require some sort of vacuum source whether it be from the turbo or intake manifold. on the side of the wastegate there will be a vacuum fitting(if there isnt one youll at least see a threaded hole where youll need to place one), that is where it needs to see pressure from either source of your choice( i prefer the IM). the fitting on the top is usually for an aftermarket boost controller. hope that helps