alright guys i got a 2003 6.0 with the garrett stage 2 Powermaxx with the batmo wheel and I'm having some issues. I installed the turbo while i had my edge juice with attitude cts and there was really no different no low end power gain and no whistle at all, i just went to a SCT and am running Vivian's Looney tune with VGT tuning for the powermaxx and am having the same issue no whistle and low end sucks, can't even spool the turbo doing a brake boost. Is there a VGT relearn needed for these turbos? I got it a few months ago brand new. Also no gain in boost only about 21lbs is what I'm seeing. If anyone knows anything that would be great thanks.