Do you have a fuel pressure guage? When was the last time you changed the fuel filter. Are you still running the stock intercooler boots? I've had trouble with them blowing off a lot less than 40 psi. I'd use a rubber pipe cap over the turbo inlet to test for boost leaks. You can get a hose clamp and 4" cap from most hardware stores. Then use one of the fittings in the intake to put compressed air into the system. About 10 psi is all you need to make leaks very obvious. Be carefull, the cap can come off some times. Put something heavy over it so it won't co flying.
