It doesnt matter what flow rates etc you have thru the exhaust turbine - pressure is pressure- as soon as the pressure reaches a certain limit the wastegate/pressure relief valve whatever u want to call it will open. I think wot u are talking about is bleed valves which fool the wastegate into thinking that the pressure is lower than it actually is - hence u get more boost before the wastegate opens. I dont think these are standard fit on production cars so there must be a difference in springing in the wastegate or if it is electronically controlled a difference in the ecu programming???

 

See reply on your original post.