how does the ssts (sequential twin-turbo setup) work?
first off, the is no #2 wastegate.there is only one wastegate and it comes off the #1 turbo because that turbo is always on line, therefore you always have a wastegate.there are 4 sets of vsv’s, actuators, and control valves for the sequential turbo system.each vsv is simply a solenoid that is either 100% open or closed, allowing manifold pressure to pressurize the different actuators that open/close the four different valves. wastegate: when the manifold reaches 11#’s of boost, the ecu sends a signal to the wastegate vsv, that allows manifold pressure to build in the wastegate actuator which opens the wastegate. exhaust gas bypass valve (ebv): somewhere around 3500 rpm, the ecu sends a signal to the exhaust gas bypass valve vsv, which allows manifold pressure to build in the exhaust gas bypass valve actuator which opens the bypass valve.this is a small opening inside the #2 turbine housing which allows some exhaust gas to go through the turbine of the #2 turbo which makes it start spi
