I posted this in the "Taste of Home" forum as well, but maybe this is a better choice. I have recently installed a Procharger on my 17' GT with a P-1x headunit, and a 3.5" Pulley. I live in Colorado and was wondering how much boost loss others at this altitude are seeing? I was under the impression that the 3.5" pulley would be good for somewhere around 12 psi at sea level, but I am only seeing between 6-7 psi at redline. I also have Kooks headers so that should also create about a 1lb loss in measurable boost, but is losing another 4ish PSI reasonable at 5500 feet?