Waste Gate question

[TraceF]

I have run across several threads where plugging the waste gate actuator hose or otherwise disabling the gate adds boost.

In simple terms, what does the waste gate do and why? What is the potential negative to disabling the waste gate?

[Idle_Chatter]

This has been debated quite a bit here, TraceF. If you search on "wastegate" you'll get about a dozen threads. Here's the latest that should answer all your questions:
http://forum.thedieselpage.com/ubb/ultimatebb.php?ubb=get_topic&f=3&t=004893