On my brother's Eclipse he's got two nozzles, one pre intercooler and one pre throttle body. The first nozzle comes on at 5 pounds of boost, the second at 10 pounds. We've seen temp drops over 100 degrees at his throttle body. (Granted, his temps are pretty hot due to how hard we're running a relatively small turbo) This has allowed him to run his turbo at its efficiency limits while retaining full timing advance all the way out to 25 pounds of boost on pump gas.

He went from gobs of knock and losing over 10 degrees of timing to a flat knock datalog.