I've been having a think about this for a while -
As a lot of people on here know, if you take the vac hose that runs from the N249 to top of DV off, you can generate some nice turbo chatter.... now I'm not saying I'm stupid enough to run round like this permanently, but I did give it a couple of minutes down the road having a play with it....
Now the N249 seems to constantly be sucking from this hose, meaning less pressure on the DV piston is required before it opens (effectively the same as using a softer DV spring)
When the hose is pulled off, (effectively stiffening the spring) the chatter is generated when coming off partial throttle, (when there is not enough pressure to open the DV) but when lifting off after harder boost, it sounds to me like the DV opens to let the majority of the pressure out (still giving a bit of chatter once closed again while the last bit of excess pressure escapes).
Now I know chatter is bad for the turbo under high boost levels, and simply plugging the DV hoses wouldn't be a wise idea, but my question is, if you simply use a stronger spring (or jimmy the hose off permenantly possibly with a n249bypass if that would keep the ECU happier) would this not effectively give the best of both worlds, giving the lovely sound of turbo chatter, but also having the DV operating on higher boost saving the turbo being given a proper caning...
I know obviously this scenario will be worse for the turbo than simply running the DV as normal, but how much worse, as the turbo will only be subject to the lower pressures being pushed backwards through it......
Hope you all manage to understand what I'm trying to say! It's getting late, so let me know if I've made a shambles of explaining this!
Ben