hamjtrucks, Did you also do the ported/coated manifold from PP or Bully Dog? To get the most out of that non-wastegate version, you need to get overall exhaust flow improvement. I have only seen the best results when someone does the manifold, a high flow muffler(s), and a turbo blanket along with that non-waste gated turbo, regardless of brand. The PP turbo is a T6 turbo like the Borg Warner 171702, the deluxe version they have is like the high end BW S400SX4-75, which is based on the 171702 turbo. They are interchangeable, but the S400 has some internal improvements. A non-wastegated turbo requires a faster exhaust flow to give the best performance. It is like taking the nozzle off of a garden hose. A wastegated version has a smaller body and acts like a nozzle on a garden hose.... by channeling the exhaust thru a smaller orifice, you get a faster flow, but you also get a lot of restriction. A non wasted gated version reduces the restriction, but you need faster overall exhaust flow to compensate. That is where the ported/coated manifold comes in, and the turbo blanket keeps it hot and flowing. And of course, the high flow mufflers are like pulling out the cork from your exhaust stacks.
It just never seems to work out quite right when you only do one thing. The only part of this puzzle that seems to give decent results all by itself, is the high flow mufflers.