Can someone explain how the gsr intake manifold dual runners work? When and how do they open? I know the ecu sends a signal to the dual runners. Are the runners open or closed before the signal is sent? Can someone explain it from point A to point B?

its a mid range rpm thing.... basically, it gives more torque before the vtec range.... i dont have more info than that though-

runners are closed at low rpm, when it activates, the other runners open to allow for more airflow at higher rpm. This all works under the theory that low rpm needs greater velocity and high rpm needs more air

Just to add the secondary runners are shorter and straighter than the primary runners. So air will take the path of least resistance. This is a good thing!

Thanks for the replies. What is keeping the runners closed? I'm guessing theres a silenoid that the ecu controls the runners to open up. Does anyone know of a website where i can look at the vacuums diagrams or read about the GSR manifold dual runners?