Not Boosting as much as my old turbo :(

[XtReMe FrOm HeLL]

so somehow my turbo blew.. i took it to a mechanic and they told me they would rebuild it... i was blowing white smoke like crazy, anyways i got another turbo with a impeller wheel installed, so today i put the turbo in.. on my old stock turbo the most i boosted was 30psi and now with this new turbo i can only get it to 20psi i have the diablo sport programmed at 100hp setting as well as a 4 inch turbo back exhaust. it also doesnt sound as whiny as the stocker did i hear a constant whoosh type sound as my boost goes up... i somewhat think i may have a boost leak.. how can i find something like that??

[whitelightning150]

is the wastegate the same as your old turbo because that could be a problem. did you talk to the guy that installed the turbo. he might know something about it