Originally Posted by cypher0117
if your car suddenly has less back pressure on the turbo you will probably overboost which can cause lean conditions and knock and then motor death.
Correct, there is no question this can be a problem, but it can be solved by changing restricter pills, running wategate boost, an ebc or mbc. Or even porting the wastegate in extreme boost creep cases.
Is there another reason? Is it a problem with boost spiking in closed loop fueling?