with cone filer for example. it allows the turbo to spool up much quicker. this puts the dv under more strain,
the standard dv are known for failing, also what u have to remember this guy is using a standard dv on a mapped car (not good) forgive me if im wrong but im sure he needs to run a yellow spring.
on my car going from uprated panel to cone makes no difference to spooling.
Happy to be educated though... have you got before and after figures?
Dvs not holding pressure, again example of my own car. Mapped to 242bhp no issues on a green spring except that coming off the boost , took a little longer. swopping to yellow snapped the boost off quicker.
the more aggressively the dv operates (harder spring) the more pressure on your turbo (not good). Its finding balance. you dont want to slam the door (instant hard pressure change) more progressively close it allowing the pressures to equalise.
Stock dvs only fail with age. The diaphram is strong enough even on my BT set up but Its usually been on the car for years prior to mapping and then fails.