well, chucked on my modded split dump(now bell mouth) and still doing to same thing, going to 17 psi at top rpm. thought it might be the bleed vale causing problems (starting to grab at straws) so took it off and plumbed hose straight from wastegate actuator to inlet pipe, still doing it although a bit slower. gunna try change the waste gate actuator with the one of my stock turbo, if that don't work, gunna pull off exhaust housing from turbo and open up the waste gate a bit