The vanes in the GTB are housed almost internally
Not saying they will close, but having thr GTB apart it seems to make sense to have the vanes open initially to add flow to the turbine, then as they close they reduce flow angle thus stopping overspeed and clipping boost levels.
Not saying they will close, but having thr GTB apart it seems to make sense to have the vanes open initially to add flow to the turbine, then as they close they reduce flow angle thus stopping overspeed and clipping boost levels.
Wishes for more power...
