There was a bit more work with the Billet pump package, but it proved not to be the problem. Moving on, OK, not the fuel system. Try running the engine as a normally aspirated engine. Remove the connection between the turbo and airbox. Believe it or not, the engine ran perfectly. Smooth as silk from 2000 RPM up to 5600 RPM where it stalled out on the prop pitch. Looks like the issue is in the turbo boost somewhere.