i have a '00 si w/ upgraded boost. about 11 1/2psi i think. maybe 14psi (yes-it actually jumped up that high before). some guy at jackson knows about it and he doesn't know what to say either. as long as it's still running good then it should be okay was the reply. haven't been paying attention for a while now. it's been about 1 year and 3 months now. with just the charger pulley too. i forgot what size pulley i have on there. might be the 4" or the 3.8". everything seems fine here. i can even play with the BTC at times to "supposedly" make it go faster. it's quick though. oh yeah, it's supposed to only be around 9 1/2psi.