This is true.If I am not mistaken and often I am, the WG is internal to the turbo housing. Change to the external WG would occur during a BT build.
thanks chris no i ment upgrading the wastegate i have a dual port plumback turbosmart bov 50/50. i want to know if i upgrade the WG will it help, or give sound or anything??This is true.
What you might be calling and wanting to replace is a Blow Off Valve it can be called a number of things sometimes referred to as a bypass valve. This is the valve that vents air back into the intake system when you let off the throttle. There are a number of company's out there that sell direct replacement ones that will bolt right onto your car. At CorkSport we run the Forge valves and have had a lot of good luck with them. They are listed here. some people run them open and others run them so they Recirculate back into the intake system like stock. We have found that there can sometimes be small running issues using a Vent To Atmosphere.
Hope this helps. If you have any other questions about it let me know.