Next test, connect high pressure port from airbox directly to the "T" into the carb float bowl pressure lines and try a run. Still didn't work. Same smooth up to 4200/4300 RPM, smooth drop to 3200 RPM, smooth acceleration up to 4300 RPM, drop to 3200, repeat. Adding further throttle just makes the cycle faster and more violent. At this point I'm at a total loss for ideas. None of the support folks I was using for help seem to want to return my e-mail requests for assistance. The engine acts like there's no turbo pressure going to the float bowls or the float bowls are loosing the pressure. But there's no physical evidence for either case. A video showing the EIS readous of the last engine run is available, but at 2:19 it's pretty big so I don't want to upload. I don't know where to go from here.