Van

Some people also use a device on the hose between the CV and the wastegate that "bleeds" some of the pressure away -- this delays the action of the wastegate when the CV tells it to open.

I'm surprised no one makes a nice billet, precise CV valve. I doubt it would be that hard and could probably be modified from some cheap idle control stabilzer (or just a little solinoid). It is one of the weakest parts in the turbo system... but still a good idea to have (for the overboost protection) on cars that don't run a MBC.