Okay, I've got all this and I've adjusted the BOV. It seems to have helped, as now I can hear the "whoosh" when I casually let off the throttle for switching gears and decelerating. The screw was all the way in before and I really had to be on it and let-off abruptly for it to open.
FYI-- The research I've done on where to source the wastegate and BOV lines has confirmed what I thought: Most stock-style hook-ups are done at the turbo for simplicity, but for the best signal it it should be sourced directly from the manifold. The signal from the turbos themselves can be altered by restrictions in the tubing and intercooler. So the pressure at the turbo is likely different than what the engine is actually seeing. If the post-turbo tubing and intercooler are in any way restrictive (which all are) it will read a higher boost than the engine. Either way works, but sourcing the vacuum at the manifold gives the absolute more precise reading than at the turbo.
I also think I have the wastegates working better, too. With an open stretch of road I was able to got WOT while in overdrive so I could watch the boost gauge. It stopped right at the 9.7# where the springs are set. So that's good. I'll start tuning for that now with the controller and carb.
It doesn't seem, however, that this has fixed the problem of the turbos producing residual boost in the bowls and flooding the engine, as previously diagnosed. My next question is this:
Why have I not seen any turbo applications with the centrifugal-style BYPASS valve in lieu of the BOV and/or Wastgates? Is it because there is something different with how the supercharger produces boost compared to the turbo, that somehow negates the use of a bypass? Or is it simply because I've never seen a turbo/blow-through at all, thus never seen the symptom or it's solution? (Maybe this isn't a problem with EFI'd turbo cars so it's never been needed) It seems like the Bypass valve would work great in a turbo application and could possibly fix the problems I'm having. There must be a reason why I've never seen it used. Have any of you guys had experience with this type of valve in a turbo application like mine? What are the pitfalls? What kind of info can you give me?