well 1st off..those centrifugal superchargers suppose to be making instant boost at the trottle...
are you sure of :
#1- your blow off (by-pass) valve is working properly and not feeding out the boost before it enters the intake.
#2- you need to count the number of COG teeth and call ATI the lst chance you get...the pulley may have it set up to starting making boost at this rpm based on someoenes else set up........they have these things set up differently for boost to come in at certain rpm's for obvious reasons..
#3- check your boost gage..they will go bad.....and where do you have your boost gage hooked up for the reading ?
just how much boost is the thing making at 5500...and when your looking at the boost gage does it automatically have 15 lbs of boost or does it start creeping up etc.......
that f1r to my knowledge is a pretty big blower...capable of producing some serious wind...
they spin at over 40,000 rpm ( internally)...its possible that you also have a broken or damaged impellar...hard to tell at this point..
call ati for sure..don't be surprised if its designed to do this....
Brian
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Bjuice..
"I'M YOUR HUCKLEBERRY ! "