I have a friend who boosted a b20 vtec and with a 57trim or 60trim one or the other at 8psi it made 258whp and like 210/220wtq tuned by scotty at mainstream. It later cracked a sleeve at that 8psi also. The sleeves are just to thin for boost. I hear 8-10psi on a smaller turbo is fine but 8-10psi with a bigger turbo is not.