holding boost until redline with my ProfecB (and have since I upgraded turbos about 12 years ago, with various boost controllers). I recently installed the new Blitz III SBC (I think that's what it's called). Even with smaller turbos (530s), I can hold high boost until 7K. Maybe an upgrade to give you alot more area under the curve (I picked up a bunch, without making more peak power). Continued success and lower ETs, Mark