from what i've read, if the turbo has an internal wastegate then the screamer pipe is useless/you don't get the same sound as with an external wastegate.

the problem is that both the exhaust exit and the internal wastegate both flow into the same chamber so the wastegate gasses are not completely cut of from the rest of the exhaust gasses

(if that makes any sense at all)

that's waht i've got to offer anyway, sure people with have different opinions, but i'd recommend listening to a car that has a screamer pipe fitted to an internally wastegated turbo, like the XS ones on ebay, and seeing how you liek the sound of that, only heard a few on youtube and they sound stupid, but i agree with you that a proper screamer pipe sounds
