I'm planning on putting a bigger exhaust on my lbz. I've heard that a 5 inch straight pipe is so big it doesn't have enough backpressure to spool the turbo. I am planning on running a straight pipe, or maybe a full flow "muffler". I have heard the 5 inch screeches at highway speed at WOT. I don't plan on adding power, and I'm not pulling anything but a boat. Anyone have suggestions? Thanks!