Do you hear any air coming out the exhaust or from your breather? DO LIKE THEY TOLD YOU, BACK THE MBC ALL THE WAY OUT BEFORE YOU BLOW YOUR ENGINE. Or just take the mbc out of the system like someone else said. Just hook up full pressure to your turbo and have someone inside the cab and let you know what is happening. If it spikes and goes up like crazy just unhook it real fast and then use your regulator, but at first get rid of that regulator, its not letting the air in fast enough. If it still isn't going up bump your engine over and try again, if that doesn't work you have a massive boost leak or big problems.